Sinclair Davidson appears to be enjoying his stint writing contrarian commentary for Crikey. I’m enjoying reading him.

But Davidson is now straying in to the perilous territory of climate change. This is a field where many pitfalls lie in wait for the uneducated commentator — as Freakonomics authors Stephen Levitt and Stephen Dubner have recently discovered. Is Davidson stumbling down the same garden path?

One of the biggest problems for contrarian commentators on climate change is getting to grips with the complexity of the subject, buttressed as it is by a vast weight of scientific evidence. Davidson, who trained in economics, appears to have only the sketchiest understanding of climate science, which is perhaps why he was prepared to write in Crikey yesterday that “it is clear, however, that statements suggesting ‘the science is settled’ can no longer be sustained” — a statement nearly identical to recent comments by arch-denialists Nick Minchin and Barnaby Joyce.

Sorry, but the science is settled, and Professor Davidson should know that. Any way you parse it, the existing scientific record overwhelmingly supports a consensus about human-caused global warming.

It’s tedious to repeat it, but here we go again. As most Crikey readers will know, the scientific consensus on climate change has developed over decades of research and thousands of peer-reviewed scientific journal publications. All the world’s major scientific bodies agree on the reality of anthropogenic global warming, and the IPCC itself is a huge committee of climate scientists who must by definition reach consensus in their publications (which is why they have “consensus” written in big letters throughout their assessments). Perhaps this is why those who question the cogency of all that scientific observation leap so quickly on supposed “gotcha” moments such as  the hacked emails from the University of East Anglia’s Climatic Research Unit, or CRU.

While the emails released via the CRU hack are certainly unseemly, they don’t invalidate the rest of the scientific community’s understanding of the global climate system. Instead, what they reveal is that some scientists resent their colleagues, are annoyed with sceptics and denialists, and can be pretty nasty in their private personal communications. That’s hardly news to anyone who has worked in science before.

The issue is not helped by the way the media has reported on the story — generally irresponsibly. The hacked emails do not expose data manipulation, and they do not show collusion or conspiracy among climate scientists, much less a big lie or a giant con. In fact, contrary to Davidson’s claim yesterday, the CRU has apparently not  “lost” or “deleted” any vital climate data. Even if it did, this wouldn’t invalidate the data gathered by NASA, the Hadley Centre, our own Bureau of Meteorology and all the other scientific observations that point to a warming planet.

To turn to specifics: the email where CRU scientist Phil Jones refers to a “trick” and to “hiding” a supposed cooling trend turns out to be boringly benign. Jones is using the word trick in a completely innocent way, in a discussion about how to draw a graph accurately. The word hiding that Davidson is so worried about actually refers to Jones not using tree ring data gathered by Keith Briffa (Briffa himself recommends not using data gathered after 1960 because of issues with comparing it observable atmospheric temperatures, as this blog post in RealClimate discusses. Science journalist Steven Andrew has also published an interview with Michael Mann, the recipient of the email from Phil Jones, which reiterates these points.

Meanwhile, other climate scientist are starting to worry about what this new cyber attack might mean. University of Chicago climate scientist Professor Raymond Pierrehumbert told Andrew Revkin of the New York Times that the attack “represents a whole new escalation in the war on climate scientists who are only trying to get at the truth”. Given the passionate and even violent sentiments to be found in denialist blogs and websites, its not surprising scientists are starting to get concerned.

Which brings us back to the danger of perpetuating half-truths and quasi-conspiracies, as Sinclair Davidson did in his article yesterday. Contrarian analysis can be refreshing and original. It can also be misleading and inconsistent. Let’s try the tactic out on Davidson himself, who has some invigoratingly sceptical views on government research funding, labelling it a “waste of money” in this 2006 monograph for the Institute of Public Affairs. “It is not clear that any substantial benefit is derived from (research grant) expenditure,” Davidson concluded in that paper. But the very next year, Davidson was awarded an ARC grant — that’s right, a peer-reviewed, government-picked winner, funded by taxpayers .

Am I playing the man here? No, just pointing out that how easy it is to take a researcher’s work out of context. That’s why the climate debate should proceed on the the basis of scientific fact, as reported in peer-reviewed publications, rather than hacked emails from a handful of scientists.