I’ve written before about the BBC and its balance. Subsequently, the BBC upheld complaints about interviewing Nigel Lawson – a non-expert – about climate science. It seems, however, that the BBC must have – as part of its charter – that any segment on climate science must include someone associated with the Global Warming Policy Foundation. Last night, on Newsnight there was a very good piece about Antarctic sea ice by Helen Czerski, followed by Evan Davies interviewing Tamsin Edwards, a climate scientist at the Open University, and Matt Ridley, an Academic Advisor to the Global Warming Policy Foundation, and not a climate scientist.

Let me make clear, though, that if this were a discussion about climate policy, I wouldn’t really have much of an issue. I might still disagree with what Matt Ridley might say, but policy is something about which many can have perfectly valid, but different, views. Science, on the other hand, is not. Typically, you do need to have some kind of actual expertise, otherwise you’re more likely to simply be making stuff up, than saying anything worth listening to.

Matt Ridley’s points were that models didn’t predict the increase in Antarctic sea ice. I don’t think this is true for all models, but so what? The climate is very complex. Some surprising things will happen. The Antarctic continent continues to lose ice mass at an increasing rate. Adding lots of fresh cold water to the surrounding sea could well contribute to increasing amounts of sea ice. It could also simply be natural variability. The record isn’t really long enough to know for sure. However, what is absolutely clear, is that an increase in Antarctic sea ice doesn’t invalidate anthropogenic global warming. We know that is happening from multiple lines of evidence.

Another point that Matt Ridley made was that the 35 year surface warming trend is lower than the mean model trends. This, I believe, is true but the 35 year trend from Cowtan and Way is 0.171 ± 0.049 degrees per decade. Even though this is below the mean model trend (which I think is around 0.2 degrees per decade) it is inside the confidence interval. So, we don’t know if this is because models really are warming too fast, because the recent slowdown in surface warming means we haven’t considered a long enough time interval, or maybe because some of the model assumptions with regards to anthropogenic emissions, volcanoes and solar have turned out to be wrong (remember, these are projections, not predictions).

Furthermore, climate models are not the only evidence we have for climate sensitivity. Paleo estimates also suggest an equilibrium sensitivity of close to 3oC. Additionally, it’s always been possible that climate sensitivity is lower than the mean (otherwise why have confidence intervals). Increasing the possibility that climate sensitivity could be low doesn’t really allow one to go thank goodness, we can relax. A true risk analysis involves considering the possibility that things could be really bad, and comparing that with the cost/risk of minimising the possibility of that outcome. Highlighting that things may be better than we think, without acknowledging that they may not, is not particularly balanced.

Representing the other side of the debate was Tamsin Edwards who I actually thought did really well. She seemed to be bristling a little at what Matt Ridley said, and tried to interject some sense. A bit tricky, though, when the other person isn’t really presenting a scientifically credible argument.

My personal view is that we really shouldn’t have experts debating non-experts about topics like climate science. It’s really too complex. On the other hand, maybe one could argue that it’s good for the public to see another side to the debate (I disagree, but others may hold different views). There is, however, another issue with Matt Ridley. Matt Ridley is actually Viscount Ridley, a member of the House of Lords and the ex-Chairman of Northern Rock. He was Chairman at a time when Northern Rock became the first British bank in over 100 years to have a run on its finances. You might imagine that he would be quite keen to stay out of the limelight after such a remarkable failure. On the other hand, you might see his current profile as being a great example of someone who’s managed to recover from such a failure.

The problem I have, though, is that you’re talking about someone who is currently holding a position that is contrary to thousands of actual experts, despite the fact that he has no formal expertise himself. Maybe he is a polymath who can understand such complex topics far better than hordes of professionals who have years of experience. Alternatively, he is an exceptionally over-confident fool. You might argue that one should ignore his past failures and judge him only on what he is doing and saying currently. I disagree. I think you can do both. I don’t know the answer for certain, but given that I’m not expecting that we’ll have to completely rewrite physics textbooks anytime soon, I’d be willing to hazard a guess.