富国须为清洁能源做好表率

As the UN conference on sustainable development begins it is the rich countries that have the most to prove. The last summit in Rio de Janeiro 20 years ago provided the opportunity for countries to sign the UN framework convention on climate change, which should have stabilised global annual emissions of greenhouse gases at 1990 levels, and placed prime responsibility on the industrialised nations, who have done most to pollute the atmosphere, to lead by example.

在联合国可持续发展大会(UN conference on sustainable development)于里约热内卢召开之际，最有必要证明自己的是富裕国家。上一次里约峰会是20年前召开的。那次峰会为各国签署《联合国气候变化框架公约》(UN framework convention on climate change)提供了机会。该公约的目标是把全球温室气体年排放量稳定在1990年的水平，并让工业化国家承担起主要责任（因为它们给大气造成的累计污染最多），为其他国家作出表率。

But rich countries have not led and annual global emissions have continued to rise. Even taking into account pledges by rich and poor nations for action by 2020, the world appears to be heading for likely global warming of 3°C or more, to a temperature not seen on earth for about 3m years.

但富裕国家却未能起到表率作用，全球温室气体年排放量仍在持续上升。即便把富国和穷国承诺在2020年前实施相应行动这一因素考虑在内，全球气温似乎也难以避免会上升3摄氏度或更多，达到约300万年来地球上未曾出现过的水平。

Having witnessed, for instance, failure by the US and Canada to honour their signatures to the Kyoto protocol, as we approach another summit, poor countries are understandably sceptical of the lofty ambitions expressed by rich nations.

穷国注意到了富国的所作所为，比如美国和加拿大都未能恪守签署《京都议定书》(Kyoto protocol)的承诺。因此，在我们召开又一次峰会之际，穷国对富国表述的宏伟抱负感到怀疑，是可以理解的。

It will take more than words to restore the confidence of poor countries. Some richer ones are dragging their feet on tackling climate change, while unfairly criticising the developing world, apparently unaware of the strides that these countries are making in finding a new path. China, India, Mexico, Brazil and other emerging powers have laid out ambitious plans to tackle deforestation and to reduce radically their emissions to output ratios. More importantly, they are implementing those plans.

若想使穷国恢复对减排事业的信心，显然不能光动嘴。一些富国在应对气候变化方面行动迟缓，同时还对发展中国家进行了不公正的批评。它们无疑没有意识到发展中国家在寻找解决气候变化问题的新途径上取得了多大的进展。中国、印度、墨西哥、巴西以及其他新兴国家，制定了对付滥砍滥伐和大幅降低排放产出比的宏伟计划。更重要的是，它们正在贯彻这些计划。

One of the biggest injustices of climate change is that the poorest countries are most exposed and vulnerable to the impacts of climate change even though they have done least to raise atmospheric levels of greenhouse gases. Now they must contend with the brutal arithmetic of a tight budget for global emissions as they try to fight poverty, develop and grow, while managing the enormous risks of climate change.

气候变化问题中最不公平的一点是，最贫穷国家面临的威胁最大，也最容易受到气候变化的影响，尽管它们在导致大气中温室气体含量升高一事上责任最小。现在，它们必须面对严厉的全球排放预算给出的苛刻目标，同时还要努力解决贫穷、发展和增长问题，并管控气候变化带来的巨大风险。

Rich and poor countries agreed in Cancún in December 2010 that global emissions should be reduced to avoid a rise in global average temperatures of more than 2°C. To have a reasonable chance of this, global average emissions have to be reduced from the present level of about 7 tonnes per capita of carbon-dioxide-equivalent to about 2 tonnes in 2050.

2010年12月，富国和穷国在坎昆一致同意，全球减排的目标应该是避免全球平均气温上升2摄氏度以上。如果想实现这一目标，那么到2050年时，全球平均排放水平必须从当前的人均约7吨二氧化碳当量降到人均2吨左右。

This is a huge challenge as developing countries will be home to 8bn of the projected global population in 2050 of 9bn. Even if the rich countries reduce their emissions to zero by 2030, developing nations would need to hold their emissions to about 5 tonnes per capita by 2030 and 2.5 tonnes by 2050. For comparison, current per capita emissions are 22 tonnes in the US, over 9 tonnes in the EU, about 7 tonnes in China, and 2 tonnes in India.

这是一个巨大的挑战，因为到2050年时全球人口预计将达到90亿，而发展中国家的人口将达到80亿。即便富国到2030年时实现零排放，发展中国家也仍需大幅降低排放水平——到2030年时降到人均5吨左右，到2050年时降到人均2.5吨。作为比较，目前美国的人均排放量是22吨，欧盟超过9吨，中国约为7吨，印度为2吨。

So rich countries not only have to accelerate their actions, but must also support the poor countries as they make the transition to low-carbon economic growth.

因此，富国不仅需要加快自身的行动，还必须支持穷国转向低碳型经济增长。

It would be morally unacceptable to try to insist that developing countries drop or scale back plans to fight poverty and raise material standards of living. The developing world is understandably suspicious that this is a hidden agenda. Yet it is a fact that their growth is the biggest source of the rise of emissions. The answer is clear: radical change in emissions per unit of output. This revolution carries many benefits: cleaner, quieter, safer, more energy-secure, and more biologically diverse energy. Rich countries must support this with technology and resources.

有些人坚决要求发展中国家放弃或缩减对抗贫困和提高物质生活水平的计划，这在道德上是无法令人接受的。发展中国家怀疑这种言论背后有不可告人的目的，也在情理之中。但同样不可否认的是，发展中国家的经济增长是温室气体排放量上升的最大源泉。解决办法很明确：彻底降低每单位产出排放量。这种革命会带来许多益处：能源会变得更清洁、更安静、更安全、供应更有保障，生物能源的种类也会变得更多。富国必须为这种革命提供技术和资源上的支持。

The developed world must not attempt to preach to poorer nations. As they deal with the largely self-inflicted damage to their economies, rich countries must show they understand the dangers that arise from hesitation in acting against climate change. They will discover by investing in the low-carbon economy, adopting clear and credible policies, and building new technologies and markets, they will help to create the only truly sustainable growth path for the future, and help find a way out of the depression of their own making.

发达国家不要试图对较贫穷国家进行说教。富国在应对自身的经济困境（这种困境在很大程度上是由它们自己造成的）之际，必须向外界表明，它们清楚在应对气候变化问题上犹豫不决带来的风险。通过投资低碳型经济、出台明确而可信的政策和开发新技术和市场，富国会发现，它们能够帮助开辟通向未来的唯一真正可持续增长之路，能够找到办法走出自己酿成的经济萧条。

Nicholas Stern is I.G. Patel Professor of Economics and Government and chair of the Grantham Research Institute at the London School of Economics. Jose Antonio Ocampo is a Professor at Columbia University and former Minister of Finance in Colombia

尼古拉斯•斯特恩(Nicholas Stern)是伦敦政治经济学院(LSE) IG帕特尔经济与政府学教授(I.G. Patel Professor of Economics and Government)、格兰瑟姆研究所(Grantham Research Institute)所长；何塞•安东尼奥•奥坎波(José Antonio Ocampo)是哥伦比亚大学(Columbia University)教授，曾任哥伦比亚财政部长