Given that I was also wanting to comment on Matt Ridley’s recent article on the benefits of carbon dioxide, I thought I might steal part of Dana’s title. Only seems fair, given that he handed the reins of his Guardian blog to Eli 😉 . Ridley’s article is based partly on an apparently peer-reviewed Global Warming Policy Foundation Report. From what I can tell, their “peer-reviewed” is the same as my “thanks for proof reading”. Matt Ridley’s article also appears to have misrepresented the views of most of the scientists that he’s quoted.
I wasn’t really wanting to discuss Matt Ridley’s article in any depth. I’ve wasted enough of my time discussing his misrepresentations, and you can always read Dana’s article if you want to know more. I was wanting to make a slightly tangential observation. It seems that one of the common justifications for articles like that written by Matt Ridley is that mainstream scientists, and the mainstream media, tend to focus on the negative aspects of climate change and, therefore, that discussing some of the positives provides some form of balance. This, however, misses the entire point of what we’re trying to do. We’re not emitting CO2 so as to change our climate; it’s simply a by product of energy generation. Consequently, the goal is to try and understand the consequences of continuing to emit CO2. It’s fundamentally a form of risk analysis and, as such, it’s entirely reasonable to focus more on the negatives then on the positives [Edit: It might have been better if I’d used cost-benefit analysis, rather than risk analysis here. I’m simply trying to highlight that it should be an overall analysis, not simply a “some good things might happen” type of analysis.].
Essentially, if there are risks associated with continued CO2 emissions, you don’t balance those risks by showing that some of the consequences might be positive. The correct comparison is between the risks associated with continuing to emit CO2 and the risks/costs associated with reducing, or stopping, our emissions. Showing that there might be some positive benefits (as there almost certainly will be) doesn’t suddenly cancel out the negatives. This would be like arguing that it’s okay to go on a potentially dangerous school trip because some of the children will have a great time.
Now, you could argue that maybe we could show that the overall benefit would be net positive. However, that’s already implicit in the standard risk analysis – the risks/costs associated with mitigation could exceed the risks/costs associated with continuing to emit CO2. However, there are a few other things to bear in mind. We’re pretty suited to our current climate, so there’s no great need to change it. Our emissions are not explictly intended to change our climate, they’re simply a consequence of our current form of energy generation. If there was a cost effective way to avoid CO2 emissions, I don’t think we would continue to do so simply because of the possible benefits of a changed climate.
Also, if you wanted to make this argument, you’d need to actually show – pretty convincingly – that the benefits would be overall positive. Climate models today are mainly scientific tools that can be used to try and understand how our climate might respond to changes. They’re also clearly stronger for some things (warming, hydrological cycle) than they are for others (regional impacts), and are clearly not suitable for designing how we might change our climate. If people think climate models are not good enough to understand how our climate responds to changes, then they’re certainly not good enough to use for geo-engineering.
So, as far as I’m concerned, these articles that promote the possible positives of climate change, simply ignore that showing that there might be some positives, is not an argument against reducing our emissions. Of course, that Matt Ridley doesn’t understand the basics of risk analysis is no great surprise.