Richard Mulgan is a former professor in the Crawford School of Economics and Government at the Australian National University. Thanks to the Canberra Times for giving space for this, concise, timely and very readable article.
Climate scepticism is good
“I am not a climate sceptic,” said Senator Nick Xenophon in a recent ABC interview, and went on to explain why. He said he found the case for human-induced global warming generally convincing, though far from certain, and believed governments should take action to reduce greenhouse emissions because of the greater risk of doing nothing.
On most everyday understandings of the term ”scepticism”, the senator was in fact displaying a sceptical attitude towards the issue: he denied that the evidence about global warming was certain and was prepared to entertain doubts about the degree of probability for global warming. His refusal to be labelled a ”climate sceptic”, however, shows how the term has become hijacked in public debate.
”Climate scepticism” now stands for a policy stance, opposition to the case for emission reduction. It has become detached from its normal sense of reasonable doubt about the science. The confusion is important and reflects a dangerous misunderstanding of how far policy can be based on robust evidence.
In principle, all scientific theories are open to falsification by new evidence and therefore no science can ever be entirely certain. In practice, however, many areas of science are sufficiently well grounded in reliable evidence to be accepted beyond reasonable doubt. But climate science is not among them.
Everyone knows the limitations of short-term weather forecasting. Climate scientists confirm that the large number of independent factors influencing climatic events rules out precise explanation or prediction. With climate change, uncertainty is compounded by the lack of reliable historical data from before the modern period. This does not mean that nothing can be known about climate change or that no predictions are worth making. But it does mean nothing can be known for certain or even with the degree of certainty that can apply in aspects of other sciences, such as physics or chemistry.
Uncertainty pervades the entire field of climate change. Scepticism should therefore be the natural attitude of any intelligent student of the topic.