The late Peter Cullen was a good friend of mine, and I helped him to establish the CRC for Freshwater Ecology, which he led so successfully. He moved my interest in the environment towards the role of rainfall and water systems, and I still regard them as the most important elements of the Australian environment, as far as those who live here are concerned. When the Co-operative Research Centre system began, in the early 1990s, it was difficult to get politicians to take a sustained interest in the environment, but that is no longer the case.
Inland water, and its management, have become a strong focus of both the Commonwealth and State Governments, along with ‘climate-change’, fires, droughts and floods. The change in twenty years is striking, and much more funding has flowed into research on the environment than was the case when I was asked to establish the Australian Research Council in 1988. The environment is always news today, and we have a political party, the Greens, for whom our relationship with the environment is central.
But these changes have brought with them another change, one which I find much less acceptable. This a shift in the core value of science, which I have always seen as the testing hypotheses against the result of experiments as a step along the way to the development of an explanatory theory, which in turn allows prediction and thereby a much greater understanding of the universe in which we live. As I see it, the scientist is innately sceptical.
As governments have become interested in science in particular areas, like the environment, they have developed policies that have built into them certain assumptions about the way things are, and these assumptions are the basis of much funding. In consequence, it becomes impolitic for scientists to write or speak sceptically about them even when the evidence suggests that the assumptions are not soundly based.
‘Climate change’ is a striking example. I put inverted commas around the term because it has been defined by the United Nations Framework Convention on Climate Change as ‘a change of climate which is attributed directly or indirectly to human activity…’ When the Convention was framed, in 1992, the role of human activity seemed paramount: there had been a strong rise in measured temperature that seemed strikingly similar to the rise in carbon dioxide accumulations over the same (rather short) period.
The urge to deal with the apparent problem through international co-operation captured people around the world and their governments, and we have had twenty years of effort to bring about a reduction in greenhouse gas emissions, which rose to 2007, and has faltered since. The agitation has brought with it the ‘scientist-advocate’, a person who has standing in the field of science concerned, and speaks out in support of government policy.
‘Scientist-advocates’ are not new — I can remember one or two in the 1940s and 1950s. But now, with the great interest in and public funding of aspects of science they seem numerous. It may seem a glamorous and exciting role, but I urge you to pass it by, and concentrate on true science, which I defined above. Why avoid it? Because science does not stand still, and the assumptions on which, for example, ‘climate change’ rests do not look as robust as they did in 1992, even though government policies have not changed.
Yes, it is true that the world is warmer than it was, but there has been no significant warming in the last 16 years. The Convention assumed that we would be able easily to distinguish human-induced warming from natural variability, but twenty years later that is still quite difficult. The predicted rise in temperature has not occurred, and predictions of perpetual drought have been dampened by two la Nina years and great floods. Sea-levels are rising, but they have been rising slowly for long time; it is not clear that they are rising any faster.
In fact, measuring all this, which seemed straightforward in the 1980s, has become more sophisticated since, and more difficult as well. All measurements come with errors of various kinds, and since we are looking at very small changes in temperature from one year to the next, or changes in sea-levels, the errors can be greater than the shift. Land temperatures are affected by where the thermometers are placed, and how many are placed. They are numerous where people live, but scarce elsewhere. Satellite observations have been available since 1979, but they are proxies, and come with their own errors.
We know a great deal more than we used to know about the climates of the world, but it is plain, at least to me, that there is a great deal more to know. Government policies like the carbon tax can have no discernible effect on the level of greenhouse gas emissions, even if every country in the world signed up to an equivalent. And when government policies are changed, as they will be when the electorate decides it has had enough of one, then the consequences can be very bad for the scientific enterprise.
There are many people for whom the need for humans to moderate their consumption of fossil fuels is akin to a religious belief. But science is not a religion, and the correct response to government should always be: ‘We don’t know, but we are able to try to find out’. Above all, scientists should never be sure, especially when the evidence is uncertain.[I was asked to provide a ‘Letter from a Friend’ to the regular newsletter of the Peter Cullen Trust, and this is my offering.]