Global Warming - From Science to Agitprop

18/07/2013 11:25 | Updated 17 September 2013

'We seem to be losing the communications battle,' the Met Office's chief scientist complained six months ago.

With global warming, science morphs seamlessly into political campaigning, Bob Ward's article, 'The Corruption of the Public Debate on Climate Change,' being a fairly typical example of the genre.

There is the obsession with secret funding sources and with the ideological motivations of non-adherents, things the philosopher Karl Popper identified as telltale signs of a pseudoscience.

Amidst all the agitprop, there is a nugget of science: no 15-year period of global temperature yields a statistically significant trend. But then, to its embarrassment, neither could the Met Office demonstrate a statistically significant trend in global temperature for the last 130 years.

That doesn't mean observed temperatures did not rise - they did - or that global warming, whether man-made or not, did not happen. Rather it illustrates the sheer difficulty in demonstrating whether the rise is outside a range of random natural variation and of moving from the physics of the test tube to the immense complexity of the atmosphere.

Bert Bolin, the first chairman of the IPCC, acknowledged that global warming was not something 'which you can prove.' In one of his last lectures, the late Stephen Schneider - one of the most intellectually able of all climate scientists - asked his students whether the science of anthropogenic climate change was settled. Dumb question, he answered. 'Climate science is not like test tube science,' Schneider said. 'You don't falsify.'

Although codified by Popper in the 1920s, falsifiability was the standard set in the Scientific Revolution and used with devastating effect by Lavoisier in his demolition of the phlogiston theory of combustion. Instead of seeking evidence that would falsify, climate science follows a much older injunction, one from the Beatitudes: 'Seek and ye shall find.'

As Popper argued, evidence can be found for virtually any proposition, so when global temperatures don't rise as anticipated, evidence is sought in ocean temperatures, sea ice extent and glacier retreat.

The absence of a falsifiability test renders the science of global warming inherently weak. Instead acceptance of the central proposition of global warming - that the earth's atmosphere is rapidly warming thanks to man's activities - marks a reversion to pre-scientific standards, principally its reliance on consensus, peer review and appeals to authority.

Computer simulations of future temperature rises cannot be verified. In the words of the mid-20th century Nobel physicist PW Bridgman, to correctly predict only has a past tense.

The provisional findings of climate science cannot explain how global warming, which was little more than a scientific curiosity for much of the 20th century, became a political phenomenon that defines our age. Indeed, the first two scientists to have quantified the effect of the Industrial Revolution on global temperatures, Svante Arrhenius and Guy Stewart Callendar, both thought global warming would be beneficial.

The explanation for global warming's potency is the rise of environmentalism, following publication of Rachel Carson's Silent Spring, arguably the single most important book since the Second World War. Environmentalists believe that in destroying fragile ecosystems, humans are imperilling their own survival.

Whilst scientists in the early 1970s signed manifestos predicting the imminent collapse of industrial civilization, the first environmental wave quickly collapsed in the economic stagnation of the 1970s. With the return of economic growth in the 1980s, global warming became environmentalism's killer app.

In 1957, the American scientists Roger Revelle and Hans Suess pointed out that mankind was carrying out a large-scale geophysical experiment. Prejudging the results of a scientific experiment is bad science, yet this one simultaneously generates powerful calls to halt the experiment before it is concluded by invoking the precautionary principle.

'What is called objectivity consists solely of the critical approach,' Popper wrote. But questioning climate science science undermines collective action to save the planet, so critics and sceptics must be marginalised and delegitmised. No one knows the outcome of the geophysical experiment. But the results of the politico-scientific experiment are now in, and include the demotion of the scientific standards established by the Scientific Revolution.

Rupert Darwall is the author of The Age of Global Warming (2013) published by Quartet Books