The way out 09 February 07

If we still have time to stabilise the climate below two degrees – and models suggest we do – then we can potentially save great swathes of global biodiversity, slow the melting of Greenland and associated sea level rise down to tolerable levels, and avoid the most dangerous positive feedbacks that would kick in as we approach three degrees of warming.

As I show in the book, in order to be 75 per cent certain of temperatures staying below the magic two-degree threshold, global greenhouse gas emissions need to peak within the next eight years. Emissions must then continue to decline, and by 2050 they must have fallen by 90 per cent. This will stabilise CO2 concentrations at around 400 parts per million (or 450 ppm ‘CO2-equivalent’ – that is, if the warming effect of all greenhouse gases like methane and nitrous oxide is expressed in CO2 terms).

Given that per-person carbon emissions vary hugely between different countries, no one should expect these percentage cuts to be adopted uniformly across the board. India, for example, currently emits about one tonne of CO2 per person, whilst the UK emits about ten. The Unites States emits double this figure, however – a whopping 20 tonnes per person. Clearly if all these countries simultaneously adopted a 60 per cent emissions cut, basic inequalities would remain: India would emit 0.4 tonnes, the UK four tonnes, and the US eight tonnes. Any cementing of structural inequality such as this is obviously highly unlikely to form the basis of a successful global emissions agreement, for the simple reason that it would be grossly unfair.

So what would work as an across-the-board global agreement, given different levels of development? There is only one logical way out of the conundrum: rich countries must agree to trade their habituated inequity in return for poor countries’ participation in an agreed climate regime, a compromise first proposed by the Global Commons Institute and known as ‘Contraction and Convergence’. Under C&C, all countries would converge to equal per person emissions allocations by an agreed date, within the overall context of a contraction of global emissions to sustainable levels. It would be a historic bargain: the poor would get equality, whilst all (including the rich) would get survival.

In order to make the system flexible and efficient, however, it is crucial that an international market in emissions permits is established – allowing poor countries to sell unused allocations to the rich, generating significant revenue in the process. This earning from a global carbon trade could help tackle poverty as well as ensuring that poorer countries have the option of pursuing a low-carbon development path.

In my view, establishing a clear political framework is surely the first step before we can begin to discuss the role of technology. Indeed, the eagerness of politicians to focus on technological options illustrates how these can be little more than a deeper step into denial. Major lifestyle changes in industrialised countries are essential if we are to stabilise the climate.

Do you agree? Does the C&C framework sound sensible and realistic? Or are there others which might work better? And am I unfairly maligning technology and inventiveness – humanity’s most powerful resource? Join the debate here.