The case for environmental scepticism

There is a strong case for informed scepticism about extreme claims of environmental threats. But excessive scepticism is seldom useful.

Those who make a powerful case for defying conventional wisdom on an important topic can always be guaranteed good press coverage. Such has been the case with Bjørn Lomborg, the Danish statistician and political scientist whose book The Skeptical Environmentalist takes a strongly critical look at the claims of prominent scientists and others that the state of the world environment is deteriorating rapidly. Such too has been the case with the Danish Committee on Scientific Dishonesty which, apparently flying in the face of the convention that critics of scientific arguments should be given a fair hearing, have condemned the book in a report published two weeks ago as being 'a perversion of the scientific method' and 'contrary to the standards of good scientific practice'.

Some have attacked this judgement as going too far in the opposite direction to Lomborg, even drawing parallels with the way that the Italian astronomer Galileo was set upon in the 17th century by those who disliked the implications of his ideas about the earth going round the sun. They have a plausible case. Lomborg's book is not intended to be a strictly scientific publication, and to judge it as such is misguided.

Essentially it is a political tract that takes aim at an inviting target — the excessive claims that are frequently made about some of the environmental dangers currently faced by humanity — and concludes that "we should not act on myths of doom and gloom". Just as many of the dire predictions made by the Club of Rome 30 years ago about the world facing the imminent depletion of major minerals has failed to come about, so too, says Lomborg, is it unlikely that some of the harsher predictions of short-term environmental catastrophe will actually happen.

A selective use of evidence

That may be true. But it is no reason in itself not to be sceptical of the views of sceptics. The Danish committee makes a powerful case for suggesting that, in forging his tightly argued case, Lomborg has been selective in his use of scientific data, highlighting that which supports his argument and minimising the significance of that which does not. This, of course, is standard practice in political argument. It is also, at least in principle, anathema to an honest scientist. The problem is that Lomborg dresses up his argument as if it is a strictly scientific one. That is where the deception lies.

In a sense, there is little new in Lomborg's book. In each of the areas that he addresses, from climate change to the loss of natural biodiversity, critics have been keen to challenge the message coming from the scientific community that urgent action is required to avoid major environmental problems. On climate change, for example, eminent scientists such as the US atmospheric physicist Richard Lindzen have pointed — correctly — to weaknesses in some of the models used to make climate predictions (see The case against human-induced climate change'and scientists' response).

What Lomborg has done is to piece together the views of these critics, turning their individual arguments into a generalised case against those scientists who are urging governments to take action. The result is a weighty indictment of the critics of science-based economic progress. Included in this are those who complain about the environmental impact of the development strategies being pursued by the developing world.

Furthermore, of immediate interest to developing countries, Lomborg argues that misguided scientific conclusions have skewed development priorities. For example, he suggests that the money required to meet Kyoto Protocol targets for reducing carbon gas emissions would be better spent on providing clean drinking water and sanitation to every human on the planet. And he confidently predicts that the problem of air pollution in developing countries will decline "when they (as we did) get sufficiently rich to stop worrying about hunger and start caring for the environment".

Mixing science and politics

This, however, is dangerous territory. For it assumes a direct correspondence between scientifically proven — or at least accepted — "facts", and the political actions which appear to flow from them. If this was the case, then flaws in the scientific argument certainly create a danger of leading to erroneous policies. And there have certainly been circumstances in which this has been true, as demonstrated by Britain's early approach to Mad Cow Disease (where a scientific consensus that the disease was unlikely to pass to humans persuaded that government that there was no need to remove infected carcasses from the food chain).

The reality, of course, is more complex. There are times when waiting for scientific 'certainty' can be its own recipe for courting disaster. Hence political enthusiasm for the so-called precautionary principle, a scientifically dubious but socially valid concept that urges politicians to play safe when there is a credible risk — even if unquantifiable — attached to a line of action (such as the introduction of a new type of chemical into the environment). Similarly, overstating a message can on occasions be an appropriate and necessary counterweight to social inertia and conventional folklore masquerading as fact — such as the idea that sleeping with a virgin can cure infection with HIV — where political action is clearly needed.

Lomborg is correct to point out that in many cases, the scientific 'certainties' claimed as the basis for environmental actions are less solid than their proponents sometimes appear to argue. He is also justified in pointing out that those advocating such actions frequently use 'worst case' scenarios as the basis of their arguments. But he is misguided in seeking a level of scientific robustness in these arguments comparable to that which is legitimately applied to papers appearing in scientific journals.

The real need for scepticism

This is both the weakness and the strength of the charge of scientific dishonesty levelled by the Danish committee. The weakness, which supporters of Lomborg have seized upon with both alacrity and enthusiasm, is that the criteria the committee applies in making its judgement of dishonesty are not entirely appropriate. Lomborg himself admits that he is not a scientific expert in any of the fields that he discusses, and that much of his source material is second-hand. Both would be crimes in an original scientific publication; but The Skeptical Environmentalist does not claim to be that, and should not be judged as such (as the committee itself admits, when it describes how Lomborg's thesis is presented in a "scientific form").

The strength of the committee's criticism, however, lies in the way that it undermines claims that Lomborg has 'proven' the dire warnings of environmentalists to be socially damaging. That is far from the case, as four prominent scientists who have been deeply engaged in these issues over many years pointed out last year in a detailed, if controversial, series of rebuttals in The Scientific American (see 'Misleading math about the Earth'). Inevitably, Lomborg's critique has been taken as solid evidence by ideological critics of government regulation, such as those who have persuaded the United States to withdraw from negotiations on the Kyoto Protocol. In fact, it is little of the sort.

Scepticism of all scientific claims is a vital element of both good science (being the essence of effective peer review) and good politics. It is particularly important when, as Lomborg points out, decisions involving massive social commitments — financial and otherwise — are involved. But the counterpart to scepticism is robustness, not precision. To the extent that Lomborg may force some of those pursuing strong regulatory objectives to reassess the scientific conclusions on which their pursuit is based, it will have achieved a valuable task. But when it seeks to undermine these pursuits by complaining of insufficient scientific precision, its value is strictly limited.

© SciDev.Net 2003