I have always been a bit uncomfortable with using purely economic arguments as a basis for prioritising public investments, and on the issue of combating climate change, it seems to me even more important that some sort of hybrid approach be adopted that is as defensible as possible, while recognising unquantifiable factors. My concern with the numbers game is that we never really have the full picture. In the end, decisions are not as robust as we'd like, and we just have to do the best we can.
The science that provides inputs to decisions on mitigation and adaptation is changing all the time, and in any case the people making decisions at COP15 can't all be expected to understand the nuances of the science, so they have to trust certain arguments and drop the others. (Or, just as likely, base their positions on their particular political realities.) That's life. But what should the negotiators - or we ourselves, for that matter - base our conclusions on, if not on a quantifiable analysis of the costs and benefits of various possible strategies?
I suggest that one of the key informants should be our sense of justice, equity and welfare. There is nothing new in that, and in fact it is the basis of much of the arguments going on in Copenhagen right now. But while justice is discussed as a basis for who should get how much funding through a UNFCCC climate agreement, and for the carbon emissions limits to be applied to different countries, I haven't heard the concept used much in debates about what the potential strategies for mitigation should be.
Economists like Sir Nicholas Stern on the one hand, and Bjorn Lomborg on the other, take opposing views on what to do about climate change, despite both trying to use rational economics to arrive at their conclusions. Clearly these arguments need to be augmented with something that will help us wade through the quagmire. For the short term, that something is probably a consideration of who is most at risk, and unable to adapt without assistance. Ultimately, though, we are all at risk, so we need to consider longer-term implications of our actions. Relying on big geo-engineering solutions is risky, in much the same way that nuclear energy has a theoretically low risk but serious impacts if something does go wrong.
Possibly the most sensible approach, and certainly one that makes intuitive sense to me, is to consider strategies that address more than one concern at the same time. Forget the big bang and go for incremental improvements that allow us to learn from mistakes without destroying life in the process. Developing renewable energy, for example, addresses the problem of peak oil while also reducing the greenhouse gas effect and the immediate health effects of emissions that are toxic or contain particulates that damage lungs. Given the uncertainties of where our climate will be in 10 or 20 years, increasing resilience is a key challenge that we should be working on, from as many angles as possible.
The December 5 edition of The Economist suggests that the technology already exists to stop climate change, even without using nuclear power, geo-engineering or carbon capture and storage. But we need to choose our approach wisely.