Why experts refuse to debate climate

Prof Steve Sherwood’s editorial republished below, appeared in The Australian on Friday, October 28. It explains why climate scientists are avoiding debates in public forums with skeptics and discusses why the scientific peer review process is the best way to deal with questions around climate change.

 

Many climate scientists now refuse to take part in public forums debating climate change because it is impossible to do justice to the science.

 

To explain why, it helps to think of the present state of climate science as if it were a high-profile and complicated murder trial that had just ended.

 

After a month of courtroom arguments and careful deliberation of the testimony and evidence, the jury announces its verdict: the accused is innocent. But not everyone likes the verdict.

 

Gnashing of teeth and unhappiness ensue. The victim's family, the police and many others want to believe the perpetrator had been arrested, and want them brought to justice.

 

Some commentators, who don't know any of the jurors, begin saying they are soft on crime, were bamboozled by crafty lawyers or suffered from a conflict of interest because the government paid jury fees.

 

A politician enters the fray, asking why the community should accept the judgment of a "monopoly" of only 12 people on such an important matter. He proposes that the verdict be disregarded and the case judged democratically instead.

 

He suggests that each solicitor present arguments and evidence on evening television, for 30 seconds. Afterwards, the people will decide, by plebiscite, based on each 30-second presentation whether the accused committed the crime.

 

It is hard to imagine how this would be regarded as fair. It is clearly a travesty of justice.

 

But climate scientists are being asked to participate in exactly this kind of arrangement when debating contrarians in public forums.

 

Debate is the lifeblood of science, but it is of a much deeper and more interactive kind.

 

The scientists who work day in and day out to understand our climate system have debated the great and small ideas for decades. They've debated in journals, at conferences, by the water coolers, by email.

 

These scientific debates are a lot like jury deliberations. It takes time to assimilate all the information, then separate the crucial facts from the noise. All participants must explain how they came to their views and lay their reasoning open to challenge. Flawed or inconsistent arguments are gradually weeded out. Across time a consensus often emerges. Climate scientists have reached that consensus.

 

More than 95 per cent of those scientists present at every step of the climate debate for significant portions of their careers agree on at least the basic point that by-products of fossil fuel burning can significantly affect climate.

 

Many, if not most of them, fear that climate change, if left unchecked, would be damaging for future generations. Given the uncertainties, nobody -- scientist or otherwise -- can confidently predict these fears wouldn't be realised.

 

It is valid that the differences in opinion on climate change should arise not with the science but with what needs to be done about its findings. In just the same way every society is entitled to a position on how murderers should be punished. These are questions of values.

 

But what we are seeing in climate change is that the matters of science continue to be questioned in "debates" long after the climate change trial has ended and the verdict reached. Scientists find themselves in the absurd situation where commentators and politicians are calling on Australians to discard the scientific consensus and decide between mainstream and contrarian views through 10-minute public debates and sound bites.

 

Of these contrarians, virtually none were present at the real scientific debates.

 

Such a position is comparable to holding a very strong opinion on a defendant's guilt without having attended the trial.

 

If you thought my earlier suggestion that solicitors would have to pack a month's trial evidence into 30 seconds was ridiculous, then imagine the task facing a climate scientist.

 

Climate scientists are asked to cram 50 years of climate science into -- if they are lucky -- a half-hour climate debate. This is the proportional equivalent of giving the solicitor three seconds.

 

In short, we are asking an expert to do as much justice to the science of climate in 30 minutes as a solicitor could do for an entire trial in just three seconds.

 

The basic physics of global warming may be simple, but the potential complications revived in perpetuity by contrarians took years for experts to sort out. They cannot be adequately explained in an hour or a day.

 

A solicitor with integrity, faced with 30 seconds to deliver trial evidence, would refuse to participate in such a scheme.

 

Climate scientists are refusing to enter public debates for exactly the same reason.

 

A system of slow, scientific deliberation that has consistently worked for hundreds of years is a far better approach to sorting out the facts of climate change than a 30-minute battle of charisma, where truth has no advantage over confabulation.

 

Steve Sherwood is co-director of the University of NSW's Climate Change Research Centre and a chief investigator in the Australian Research Council's Centre of Excellence for Climate System Science.

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