I've just returned from Canada, where I've been involved in efforts to stop the government's disastrous campaign of sabotage against the Copenhagen climate talks. I don't know whether or not I've helped to make a difference – you never do – but I did manage to get the message into most of the major media, and my attacks on Canada's record have kicked off a lot of discussion. Sometimes it helps to have a foreigner criticising your national policy, as it shows that your government's actions haven't gone unnoticed overseas.
I got involved in quite a few talks and debates while I was there, culminating in a showdown with Lord Nigel Lawson and Bjorn Lomborg. On my side was Elizabeth May, leader of the Canadian Green party. You can watch it on the Munk Debates site.
The motion was that "Climate change is mankind's defining crisis, and demands a commensurate response."
Broadly speaking, the other side argued that our money would be better spent by other means. Lawson was relatively easy to handle, not least because he said some pretty daft things, such as: "There has been no further global warming this century." When I pressed him on this, he said his contention was supported by the HadCRUT3 temperature series. What it actually shows is that eight out of the 10 warmest years since records began have occurred since 2001.
Lawson, of course, was deploying that tired old trick of cherry-picking his starting date. If you begin the series at 1998, you might indeed conclude that temperatures have fallen, since 1998 was the hottest year ever recorded. But if you begin with 1997 or 1999 or any other year in the 20th century, you discover that there has been plenty of global warming this century. That wasn't the most sophisticated ruse, was it?
Lomborg was a tougher nut to crack. He was extremely skilled at framing the debate to keep the discussion on his territory: namely a rigid cost-benefit analysis, informed, in my view, by wildly inaccurate figures. He was helped by the wording of the motion, with which he made great play.
Though Elizabeth and I kept trying to bring the debate back to what we wanted to talk about – the science and the human impacts – Lomborg ensured that much of it centred around discussing exactly how much climate change would cost to prevent and how much it would cost to live with. I talked about the Stern review, he talked about his Copenhagen consensus, but it meant that the discussion got stuck on the question of which figures the audience should believe rather than on the more important question of what climate change was likely to do, and how we could stop it. There was an "oh no it isn't, oh yes it is" quality to the debate, which doesn't exactly help to move the issues on.
The result was that no one was able to deliver a knockdown blow. In the hall, the audience shifted a few percentage points in our opponents' direction; in the live webcast, a few percentage points towards us. It was a stalemate.
That was quite a contrast to my debate with James Delingpole last night. Hosted by Index on Censorship, we were discussing "Saying the unsayable: Is climate scepticism the new Holocaust denial?". Index filmed it and will put it up on their site soon.
Though James had begged his supporters "Please come and give your support. I'll be so much better if I'm playing to a friendly crowd," and plenty of them turned up, it was like shooting rats in a bucket, as poor James just seemed to make life harder for himself every time he opened his mouth.
For instance, when I asked him for an example of the unacknowledged Einstein who could blow the entire science of climate change away, yet who has been suppressed by the peer review process, he proposed the retired geologist Nils-Axel Morner, who claims to have proved that sea levels are falling, not rising.
As the scientist Tim Lambert points out, Morner, who has taken samples in the Maldives, "completely ignored all direct measurements of sea-level from tide gauges and satellites", using a series of indicators that were only indirectly related. The body he used to work for, the International Union for Quaternary Research, has asked that it be dissociated from his claims. It's as if James had cited the Daily Mail columnist Melanie Phillips as the genius who has proved that autism is, after all, caused by the MMR injection.
So now I want some advice: with the benefit of hindsight, how could I have handled Bjorn Lomborg better? What arguments would you have used, and what would your debating strategy have been? Please watch the debate and let me know.