Q&A session, which appeared in The Independent, published in September 2010.

Can we cut carbon in time?

Yes. If we really want to. If all our current carbon intensive vehicles, power stations, factories and other sources of carbon dioxide were replaced by zero carbon technologies at the end of their lives we could keep the concentration of carbon dioxide below the level necessary to give us an evens chance of avoiding dangerous climate change. This was the conclusion of a recent study published in Science.

All the zero carbon technologies we need are already available or within reach. Deploying them would take the kind of effort normally only mobilised in wartime. And we would have to do it on a global scale. But the necessary technologies, engineering capacity and skills are there if we want to use them.

Wouldn’t this wreck the economy?

No. On the contrary. It would provide exactly the kind of stimulus necessary to prevent the current recession turning into a depression. It was the stimulus of the Second World War that ended the depression of the thirties and laid the foundations for the fifty years of growth that followed. Government economic policies then, as now, were too feeble on their own.

The International Energy Agency has calculated that $26 trillion will need to be invested by 2030 to meet the world’s growing need for energy. The additional cost of making this energy low, rather than high, carbon would be $10 trillion. This sounds like a lot of money but taking the low carbon route would avoid nearly $9 trillion of spending on oil. So the net cost would be a little over $1 trillion over twenty years, or some $60 billion a year. Peanuts compared to the bank bailouts.

So what’s the problem?

The politics. Going low carbon will not wreck the economy but it will wreck some very big businesses. To keep the climate safe we need to arrive at a carbon neutral energy system by 2050. By that time, no-one will be driving vehicles with fuelled by petrol. So what will the oil companies be selling you?

Dealing successfully with climate change means unzipping the business model of many of the world’s largest and most politically engaged businesses. They will resist. Actually, they are already resisting. As is often the case, the few large business losers will shout a lot louder than the seven billion human winners.

Too difficult. Wouldn’t we be better off getting on with geo-engineering?

No. Why would you ever imagine that it would be easier to get agreement about something we do not know how to do than it is to get agreement about something we do know how to do? This only sounds like a prudent back-up. It is actually a recipe for business as usual and thus for catastrophe.

Oddly, quite a few of those people who think that climate models are not reliable enough to warrant spending billions reducing emissions seem to think they are good enough to justify spending  billions removing carbon from the atmosphere.

So what will happen at Cancun?

Not much. Certainly not enough to keep the headlines buzzing. Much blame for the debacle in Copenhagen has been placed on the complexity of the UN process. This misses the point. The main reason Copenhagen failed was lack of political will. Politicians determine outcomes, not processes. When they find processes getting in the way of something they really want politicians ignore, by-pass or innovate around the obstacles.

The political will is still not there. Actions always speak louder than words. Whatever we say, unless low carbon energy investment is rapidly overtaking high carbon energy investment we are not serious. If we are not serious, why should we expect others to be? It is not yet, so we are not yet.

Does that make Cancun irrelevant?

No. To solve the climate problem we must get to a defined point by a defined time – a carbon neutral global energy system by 2050. Getting a legally binding global agreement does not guarantee success but it does improve the chances compared to adding up the promises each nation separately makes then getting into a succession of fraught burden sharing arguments if they don’t get us there fast enough.

An international treaty is the output of a political bargain, not an input to it. It codifies what countries are willing to do and so raises the price, and lessens the likelihood, of it being broken. But first countries have to be willing. That means active diplomacy in capitals to create more political space for the negotiations in Cancun