Thursday, March 29, 2007

Prospect - a response

David Whitehouse, once a science reporter for the BBC, has responded to my denunciation of ‘climate sceptics’ in Prospect. Here are his comments – I don’t find them very compelling, but you can make up your own mind:

"Philip Ball veers into inconsistent personal opinion in the global warming debate. He says the latest IPCC report comes as close to blaming humans for global warming as scientists are likely to. True, its summary replaced “likely to be caused by humans” with “very likely”, but that is hardly a great stride towards certainty, especially when deeper in the report is says that it is only “likely” that current global temperatures are the highest they’ve been in the past 1,300 years.
As for “sceptics” saying false and silly things, Ball should look to the alarmist reports about global warming so common in the media. These “climate extremists” are obviously saying false, silly things, as even scientists who adhere to the consensus have begun to notice. And it’s data, not economics, that will be the future battleground. The current period of warming began in 1975, yet the very data the IPCC uses shows that since 2002 there has been no upward trend. If this trend does not re-establish itself with force, and soon, we will shortly be able to judge who has been silliest.”

The first point kind of defeats itself: by implying that the IPCC’s move towards a stronger statement is rather modest, Whitehouse illustrates my point, which is that the IPCC is (rightly) inherently conservative (see my last entry below) and so this is about as committed a position as we could expect to get. If they had jumped ahead of the science and claimed 100% certainty, you can guess who’d be the first to criticize them for it.

Then Whitehouse points out that climate extremists say silly and false things too. Indeed they do. The Royal Society, who Whitehouse has falsely accused of trying to suppress research that casts doubt on anthropogenic climate change, has spent a lot of time and energy criticizing groups who do that, such as Greenpeace. I condemn climate alarmism too. Yes, the Independent has been guilty of that – and is balanced out by the scepticism of the right-wing press, such as the Daily Telegraph. But Whitehouse’s point seems to be essentially that the sceptics’ false and silly statements are justified by those of their opponents. I suspect that philosophers have got a name for this piece of sophistry. Personally, I would rather than everyone try harder not to say false and silly things.

I don’t know whether Whitehouse’s next comment, about the ‘current warming’ beginning in 1975 is false and/or silly, or just misinformed. But if it’s the latter, that would be surprising for a science journalist. There was a warming trend throughout the 20th century, which was interrupted between 1940 and 1970. It has been well established that this interruption is reproduced in climate models that take account of the changes in atmospheric aerosol levels (caused by human activities): aerosols, which have a cooling influence, temporarily masked the warming. So the warming due to CO2 was continuous for at least a century, but was modified for part of that time by aerosols. The trend since 1975 was thus not the start of anything new. This is not obscure knowledge, and one can only wonder at why sceptics continue to suppress it.

As for the comment that the warming has levelled off since 2002: well, the sceptics make a huge deal of how variable the climate system is when they want to imply that the current warming may be just a natural fluctuation, but clearly they like to cherry-pick their variations. They argue that the variability is too great to see a trend reliably over many decades, but now here’s Whitehouse arguing for a ‘trend’ over a few years. Just look at the graphs and tell me whether the period from 2002 to 2006 can possibly be attributed to variability or to a change in trend. Can you judge? As any climatologist will tell you, it is utterly meaningless to judge such things on the basis of a few years. Equally, we can’t attach too much significance, in terms of assessing trends, to the fact that the last Northern Hemisphere winter was the warmest since records began. (Did Whitehouse forget to mention that?) But that fact hardly suggests that we’re starting to see the end of global warming.

“Who has been silliest” – OK, this is a rhetorical flourish, but writers should pick their rhetoric carefully. If the current consensus on a warming trend generated by human activity proves to be wrong, or counteracted by some unforeseen negative feedback, that will not make the scientists silly. It will mean simply that they formed the best judgement based on the data available. Yes, there are other possible explanations, but at this point none of them looks anywhere near as compelling, or even likely.

My real point is that it would be refreshing if, just once, a climate sceptic came up with an argument that gave me pause and forced me to go and look at the literature and see if it was right. But their arguments are always so easily refuted with information that I can take straight off the very narrow shelves of my knowledge about climate change. That’s the tiresome thing. I suppose this may sound immodest, but truly my intention is just the opposite: if I, as a jobbing science writer, can so readily see why these arguments are wrong or why they omit crucial factors – or at the very least, why the climate community would reject them – then why do these sceptics, all of them smart people, not see this too? I am trying hard to resist the suspicion of intellectual dishonesty; but how much resistance am I expected to sustain?
When it’s right to be reticent

[This is the pre-edited version of my latest article for]

The caution of climate scientists is commendable even if caution is out of fashion.

Jim Hansen is no stranger to controversy. Ever since the 1980s he has been much more outspoken about the existence and perils of human-induced climate change than the majority of his scientific colleagues. A climate modeller at NASA’s Goddard Institute for Space Studies in New York, Hansen has flawless credentials to speak about climate change – and his readiness to do so has led to accusations of political interference and censorship (see here).

But his views haven’t only ruffled political feathers – they have dismayed other scientists too, who are uncomfortable with what they see as Hansen’s impatience with science’s inherent caution.

So in some ways, Hansen’s latest foray will surprise no one. In a preprint submitted for publication, he claims that “scientific reticence” is seriously underselling the potential danger that climate change poses – specifically, that it “is inhibiting communication of a threat of potentially large sea level rise.” Because disintegration of polar ice sheets is poorly understood, it is very difficult for scientists to make a reliable estimate of the likely future changes in sea level. As a result, Hansen charges, they have put figures on those aspects of sea-level rise they can estimate with some confidence, but have refrained from doing so for this key ingredient of the problem, giving the impression that the probable changes will be much smaller than those Hansen considers likely.

The responsibility for pronouncing on such issues falls primarily on the Intergovernmental Panel on Climate Change (IPCC), which Hansen regards as conservative. This, he admits, contributes to IPCC’s authority and is “probably a necessary characteristic, given that the IPCC document is produced as a consensus among most nations in the world and represents the views of thousands of scientists.” The most recent IPCC report has been characterised as the most strongly worded yet, but its conclusions apparently still required much negotiation and compromise.

And yet Hansen believes that “Given the reticence that IPCC necessarily exhibits, there need to be supplementary mechanisms” for communicating the latest scientific knowledge to the public and policy makers. He calls for a panel of leading scientists to “hear evidence and issue a prompt plain-written report” on the dangers – which clearly he envisages as a much more forceful statement about impending climate catastrophe and the need for immediate action to “get on a fundamentally different energy and greenhouse gas emissions path”.

This is a strange proposal, however. Basically, Hansen is calling on the scientific community to collect their scientific thoughts and then to speak out unscientifically – which is to say, without the caveats and caution that are the stock-in-trade of good science. However, Hansen points out that in fact scientists do this all the time – when they are talking among themselves. He recalls how, challenged by a lawyer acting on behalf of US automobile manufacturers to name a single glaciologist who agreed with his view that ice-sheet break-up would cause sea-level rise of more than a metre by 2100, he could not do so. Even though he had heard plenty of such scientists express deep concerns to this effect in private exchanges, none had said anything definitive in public.

Why wouldn’t they do that, if it’s really what they thought? Hansen posits what he call a “John Mercer effect”. In 1978 Mercer, a glaciologist at Ohio State University, suggested [1] that anthropogenic global warming could cause the West Antarctic ice sheet to disintegrate and sea level to surge by over 5 m within 50 years. Mercer’s paper was disputed by other scientists, who were generally portrayed as the sober and authoritative counterbalance to Mercer’s “alarmism”.

“It seemed to me”, says Hansen, “that the scientists preaching caution and downplaying the dangers of climate change fared better in receipt of research funding.” This reticence, he suggests, is encouraged and rewarded both professionally and financially.

Hansen says he experienced this himself in the early days of climate-change research. He was one of the first to point out, in a paper coauthored in 1981, that rising levels of atmospheric carbon dioxide could be linked to a warming trend throughout the twentieth century [2]. At that time the trend itself wasn’t so clear – the globe was only just emerging from a three-decade cooling spell, now known to be caused by atmospheric aerosol particles that temporarily outweighed the greenhouse-gas contributions.

But by 1989 Hansen was prepared to state with confidence that we could already see the effects of human-induced greenhouse warming in action. His colleagues felt this was jumping the gun – that it was still too early to rule out natural climate variability.

This history is instructive in the face of common claims from ‘climate sceptics’ that climate scientists play up the threat of global warming in order to secure funding. Anyone who witnessed (as I did) the slow and meticulous process that brought climate scientists from this position in the late 1980s to what is effectively a consensus today that human-induced climate change is almost certainly now evident will recognise the nonsense of the sceptics’ claim. The dogged reluctance to commit to that view in the late 1980s [3] looks rather remarkable now; but it was correct, and the community can regard its restraint with pride.

Yet it also means that Hansen was in a sense right back then. Such retrospective vindication, however, is not in itself justification. He could just as easily have been wrong. His views may have been based on sound intuition, but the science wasn’t yet there to support it.

All the same, Hansen is right to say that “scientific reticence” poses problems. He points out that, because the climate system is nonlinear (and in particular, because there are positive feedbacks to ice-sheet melting), excessive caution could end up sounding the alarm too late. Possibly it already has.

The question is what to do about that. But the real issue here is not that scientists are “reticent” – it is that the public, politicians and leaders are not accustomed to reasoning and debating as scientists do. It is within the very grain of science – Popper’s legacy, of course – that it advances by self-doubt. The contemporary culture, on the other hand (and probably it has never been very different), favours dogmatic, absolute statements, unencumbered with caveats. If they prove to be wrong, no matter – another equally definitive statement will blot out memory of the last one. Thus you can say something such as HIV does not cause AIDS, or there is no such thing as society, and still be taken seriously years later as a commentator on current affairs.

The moment it abandons its caution and claims false certainty, science loses its credibility; indeed, it ceases to be true science. This is not to say that scientists should commit to nothing for fear of being proved wrong. Nor is it by any means a call for scientists to step back from making pronouncements that guide public policy – if anything, they should do more of that. But when they are talking about scientific issues, scientists cannot afford to abandon their (public) reticence. It is as individuals, not as community spokespeople, that they should feel free, as Hansen rightly does, to voice views, intuitions and beliefs that reach beyond the strict confines that science permits.

1. Mercer, J. Nature 271, 321 – 325 (1978).
2. Hansen, J. et al. Science 213, 957 – 966 (1981).
3. Kerr, R. Science 244, 1041 – 1043 (1989).

Friday, March 16, 2007

More noise from the markets

Those wacky economic analysts are at it again. Since I enjoy Paul Mason’s cheeky-chappie appearances as the business correspondent on BBC2’s Newsnight, and because I am told he is indeed a nice chap, I don’t wish to cast aspersions. But his article on the world economy in New Statesman last week (12 March, p.16) showed the kind of thing that passes as routine in the world of quotidian economics. “When the world’s most powerful people gathered amid the snows of Davos in late January, there was a tangible warm glow being given off by the economic cycle… Six weeks later, the financial markets are in turmoil and what was first shrugged off as a ‘correction’ is being seriously monitored as a potential crash.”

OK, so the forecasts were wrong again. Big news. And so the ‘cycle’ somehow stopped ‘cycling’ (or, as economists would say, the cycle changed earlier than expected, which their ‘cycles’, uniquely in science, are permitted to do). Big news again. But get this as the ‘explanation’ offered by the head of strategy at the consulting firm Accenture: “People had undervalued risk, assuming that because the economy is benign there’s not going to be volatility.” I love it. These impressive words – “undervaluing risk”, overlooking “volatility” – translate to something simple: “people forgot that the economy fluctuates”. People thought that because things were good, they were going to stay good.

Now, the idea that market traders were unrealistically optimistic is not especially shaming for them. This is just Keynes’ old “animal spirits” at work, as ever they are. But what a weird situation it causes when analysts are called upon to explain the consequences. These savants, whose salaries would make your eyes water, sagely pronounce, “ah yes, well the market did something unexpected because traders guessed wrong. They imagined that the market was not going to fluctuate, though it always does.” Ah, thanks for clearing that one up.

At root, this transmutation of the bleeding obvious into lucrative analysis stems yet again from the fact that market agents behave in a way that we all recognize as thoroughly human and natural, but which is not permitted in traditional economics. So to those who monitor and interpret the economy, it looks like wisdom of the highest order.

Tuesday, March 13, 2007

Can you tell true art from fake?

Well, find out. Mikhail Simkin at UCLA (whose work on 'false citations' in the scientific literature is highly revealing about the laxity that exists in checking sources) has put a test online in which you are invited to distinguish between some paintings by Modernist 'greats' such as Klee, Mondrian and Malevich, and "ridiculous fakes" that Simkin has mocked up. So far, over fifty thousand people have taken the test, and Simkin has now revealed the results. Surprise: on average, people identify about 8 out of 12 pictures correctly. In other words, they do better than random guessing, but not by much.

What does that mean? The cynic would say that it shows that 'modern' art is mostly a matter of the Emperor's new clothes: detach the great names and we often can't tell if we're looking at genius or doodling. That, of course, is a very old story.

But it would also be a simplistic one. Actually, I was surprised by the choices Simkin made for the test. Several of the images are obviously computer-generated. And most of not all of the true 'great works' would be recognized by anyone with a reasonable knowledge of 20th century art. I got one wrong, suspecting a 'fake' to be 'real'. But this didn't mean I was particularly impressed by the fake. Nor am I all that impressed by some of the 'reals'.

And it seems Simkin has a curiously old-fashioned notion of 'modern art', appearing to equate it with Modernist painting that is mostly almost a century old. Why not try the same thing with, I don't know, Hirst or Ofili or Gary Hume (if you insist on making art = painting in the first place)? You might find the same results, but at least they'd feel a bit more relevant.

Besides, are you really judging a Malevich by looking at a small and rather low-quality image on a computer screen?

The key point, though, is that underlying Simkin's test seems to be the notion that 'real art' would be instantly identifiable because it would show great skill, which would somehow render it timeless and universal. I'm not going to rehearse the case against that reactionary position, except to say that the galleries are full of paintings from previous ages rendered with consummate skill that seem to us now to be dull, irrelevant, pointless and conservative (which isn't to say that they are – although they might be – but only that times have moved on). Besides, the quality of art isn't something that is decided by democratic vote. Sorry about that seemingly elitist notion, but it has to be true. If it wasn't, artists might as well give up and abandon the stage to people who paint pretty watercolours.

It is true that the pomposity of the art world needs pricking, and often. Contemporary art often now seems to be awarded greatness by media cravenness, self-promotion, and the vagaries of the Matthew principle (the rich get richer). There's a great deal of silliness about, mostly thanks to the sad infatuation with celebrity that Western culture is passing through (well, I'm an optimist). But replacing critical judgement with vox pop ballots seems likely to merely pander to that, not to challenge it.

All the same, Simkin's paper is great fun to read. I only hope it triggers discussion rather than sneering.

Friday, March 09, 2007

If addiction's the problem, prohibition's not the answer

[This is the pre-edited version of my latest muse article for Nature's online news.]

China's ban on new internet cafés raises questions about its online culture

The decision by China to freeze the opening of any new Internet cafés for a year from this July has inevitably been interpreted as a further attempt by the Chinese authorities to control and censor access to politically sensitive information.

China defends the ban on the grounds of protecting susceptible teenagers from becoming addicted to games, chatrooms and online porn. Yu Wen, deputy of the National People's Congress, has been quoted as saying "It is common to see students from primary and middle schools lingering in internet bars overnight, puffing on cigarettes and engrossed in online games."

The restriction on internet cafés will certainly assist the Chinese government's programme of web censorship (although there are already more than 110,000 of these places in China). But to suggest that the move is merely a cynical attempt to dress up state interference as welfare would be to overlook another reason why it should be challenged.

It’s quite possible that the government is genuinely alarmed at the fact that, according to a recent report by the Chinese Academy of Sciences, teenagers in China are becoming addicted to the internet younger and in greater numbers than in other countries. The report claimed that 13 percent of users played or chatted online for more than 38 hours a week – longer than the typical working week of European adults.

Sure, you can try to address this situation (which is disturbing if the figures are right) by limiting users' access to their drug. But anyone involved in treating additive behaviour knows that you'll solve little unless you get to the cause.

Why is the cyberworld so attractive to Chinese teenagers? It doesn't take much insight to see a link between repression in daily life and the liberation (partly but not entirely illusory) offered online.

Yet it would be simplistic to ascribe the desire to escape online with the political oppression that certainly exists in Chinese society. After all, there are more oppressive places in the world. Indeed, it is arguably the liberalization of Chinese society that adds to the factors contributing to its internet habit.

There is in fact a nexus of such factors that might be expected to prime young people in China for addition to the net: among them, the increase in wealth and leisure and the emergence of a middle class, the replacement of a demonized West with a glamorized one (both are dangerous), the conservatism and expectations of a strongly filial tradition, the loneliness of a generation lacking siblings because of China's one-child policy, and the allure and status of new technology in a rapidly modernizing society.

Stephanie Wang, a specialist on Chinese internet regulation at the Berkman Center for Internet and Society at Harvard Law School, suggests that the problems of internet use by young people may also simply be more visible in China than in the West, where it tends to happen behind the closed doors of teenagers’ bedrooms rather than in public cybercafés. Wang adds that the online demographic in Asia is more biased towards young people, and probably more male-dominated.

The Chinese government hardly helps its cause by justifying internet control with puritanical rhetoric: talk of "information purifiers", "online poison" and the need for a "healthy online culture" all too readily suggests the prurient mixture of horror and fascination that characterizes the attitude of many repressive regimes to more liberal cultures. But let's not forget that much the same was once said in the West about the corrupting influence of rock'n'roll.

And anyway, surely youth has always needed an addition. In a culture where alcohol abuse is rare, drug use carries terrifyingly draconian penalties, sexuality is repressed and pop culture is sanitized, getting your kicks online might seem your only option. As teenage vices go, it is pretty mild.

As with all new technologies, from television to cell phones, the antisocial behaviour they can elicit is all too easily blamed on the technology itself. That's far safer than examining the latent social traits that the technology has made apparent. In this regard, China is perhaps only reacting as other cultures have done previously.

So rather than adding more bricks to its Great Firewall, or fretting about youngsters chain-smoking their way through the mean streets of Grand Theft Auto, China might benefit from thinking about why it has the addition-prone youth cyberculture that it claims to have.