2014年经济学人 气候变化，全球担心（在线收听）

China, India and climate change

Take the lead

Emerging markets are a big part of the problem; they are essential to any solution

Greenprint: A New Approach to Cooperation on Climate Change. By Aaditya Mattoo and Arvind Subramanian.

MOST books about the environment take the West as their starting point. This is understandable. For decades America was the world's biggest polluter, contributing more to the problem than any other country, whereas Europe—at least in its politicians' minds—has model environmental laws and holds plenty of righteous talks to negotiate new solutions.

But Europe and America are becoming supporting actors in the world's climate-change drama. The lead players are China and India. China is the world's largest emitter, contributing nearly a quarter of current global emissions. With India it accounted for 83% of the worldwide increase in carbon emissions in 2000-11. Though global warming began with industrialised countries it must end—if it is to end—through actions in developing ones. All the more reason to welcome “Greenprint”, the first book on climate change to concentrate on this growing part of the problem. Written by Aaditya Mattoo, an economist at the World Bank, and Arvind Subramanian, a senior fellow at the Centre for Global Development, the book offers an unflinching look at what one might realistically expect emerging markets to do.

From an environmentalist's point of view, India and China elicit despair. They are obsessed with growth. To fuel it, they are building ever more coal-fired power stations, a filthy form of energy. Their cities fume. Their rivers catch fire. There is not much anyone can do about it.

But an attractive quality of this book is that it goes beyond such fatalism. The West, the authors argue, has failed to mitigate global warming, so developing countries will have to take over. This is necessary, they say, because global warming will affect developing countries more than rich ones, partly because tropical and subtropical lands are more sensitive to warming than cold or temperate ones, and partly because rich people can afford better flood controls and drought-resistant seeds than poor ones. One estimate by William Cline, an economist, found that a rise of 2.5% in global temperatures would cut agricultural productivity by 6% in America but by 38% in India. In light of their disproportionate vulnerability, emerging giants will have to push rich countries to make more environmental compromises. To make these demands credible, they themselves will have to make some changes too.

The trouble, as the authors admit, is that emissions cuts will also be costly for China and India. Messrs Mattoo and Subramanian estimate that if the two countries were to reduce emissions by 30% by 2020 (compared with doing nothing), their manufacturing output would fall by 6-7% and their manufactured exports by more than that. As still relatively poor countries, they are less able to bear the pain.

These challenges help to explain why it is so difficult for India and China to take the lead on climate change. After considering different ways to allocate emissions cuts among nations, the authors concede that the fairest approach would be to allow developing countries to consume as much energy as rich ones did during their own industrial revolutions. But if the aim is to limit the rise in global temperatures to two degrees, which most scientists think necessary, this would allow developing-country emissions to rise by 200% whereas rich-country emissions would have to fall by an amount that is politically inconceivable.

The authors supply more reasonable solutions. They reckon that China and others could and should invest more in new technologies, such as carbon capture and storage, in order to boost improvements in clean energy. They also provide a detailed and convincing case for rich countries to put a price on carbon by introducing a modest border tax on imports from developing countries.

The book does not quite provide the promised “greenprint” for developing countries to reduce emissions. But that would be a tall order. As a first stab at analysing one of the world's most intractable problems, it provides a wealth of analysis and fuel for thought.