Contraction and Convergence

Aubrey Meyer

The idea of Contraction and Convergence is at the same time both simple yet radical. It is a way of deciding how much each citizen of the world should be allowed to consume if we are to tackle environmental problems, and is usually applied to the amount of carbon dioxide we should each be allowed to put into the atmosphere if we are to reduce emissions. It is effectively a way of rationing, and was dreamed up by Aubrey Meyer, a South African violinist now living in London, who has gone on to found the Global Commons Institute.

When Meyer first put forward his idea it was dismissed as too radical or “communism”, but it has gone on to form much of the negotiation at the level of the United Nations over how greenhouse gas emissions can be reduced. The reason contraction and convergence is radical is that it proposes the concept of fair shares, essentially that every person on the planet is entitled to a ration of emissions. The crunch comes when you grasp the fact that citizens of the developed world, who generally consume far more than their “share”, will have to consume less, and the citizens of the developing world, who generally emit very few greenhouse gas emissions, will be allowed to consume more, as their nations adopt a more affluent lifestyle.

There are obviously complications that the theory of contraction and convergence has had to answer, so that it has had to propose that developing nations should also have to cap their population growth to overcome the incentive to boost their population to get a bigger share. There is also the issue of how the overall ration is set. This depends on what is a safe level of carbon dioxide in the atmosphere, which is a question that even the top scientists of the Inter-governmental Panel on Climate Change (IPPC) cannot definitively answer. Some say that 550 parts per million (ppm) of carbon dioxide is a safe level, before there is a risk of positive feedbacks that create runaway global warming that leaves us with an uninhabitable climate like that on Venus. Others say that 450 parts per million is the dangerous level. At the present time the level of carbon dioxide in the atmosphere is rising fast at about 383 ppm, and at the current rate of growth of emissions from industrialised and developing nations, and our love of driving and flying, there is no prospect of limiting the concentration to 450 ppm unless the world undergoes some kind of overnight revolution in consciousness and lifestyle, that seems unlikely. We are therefore engaging in a huge gamble with the future of planet Earth. Contraction and convergence is a possible solution, but it may come too late. The reason some in the developed world see contraction and convergence as a dangerous idea is that instead of let us get away with changing a few lightbulbs and doing a bit of recycling, it means consuming less, and even, shock horror, giving up flying and driving.