China's climate change promise opens the way for global deal

China has sent countries sitting on the sidelines of international climate change negotiations a powerful message. Its pledge to substantially cut carbon dioxide emissions by 20 per cent more than previously indicated lifts expectations others will make similar promises. With common ground having been found with the European Union and the US, momentum for an agreement is building. That amounts to the best hope yet of a meaningful deal being struck at UN talks in Paris in December.

The goals laid out by Premier Li Keqiang in Paris on Tuesday are ambitious. Adding to a landmark agreement with the US announced in Beijing last November, China aims to cut carbon emissions per unit of GDP by 60 to 65 per cent of 2005 levels by 2030. It has already promised to reduce those amounts by between 40 and 45 per cent before the end of the decade. A long list of measures was announced to attain these aims.

Coal, accounting for 67 per cent of power production, will be used more efficiently and in lesser amounts. Development of gas, nuclear, hydro, solar and wind power will be increased, emissions from buildings and transport cut and more forests planted. The commitment to launching a national carbon market by the middle of next year will be strengthened, while greater emphasis will be put on the search for cleaner energy. This fits national as well as international interests; ridding cities of harmful air pollution is as much a priority as global warming.

The task is challenging in the extreme. China will need to maintain its decarbonisation rate of about 4 per cent a year until 2030, the target for emission levels to peak. Few countries have attained such a sustained figure - Russia was among the few in the 1990s due to the drop in industrial output following the collapse of the Soviet Union. Yet China, through will and determination, could bring that date forward if the present trajectory is maintained.

China is by far the world's biggest producer of the greenhouse gases that cause temperatures to rise, alter weather patterns, melt polar ice and raise sea levels. The failure of climate talks in Copenhagen in 2009 was in part due to the biggest polluters, China and the US, rejecting the idea of binding emissions cuts. That stance changed last year and Beijing, through its latest commitment, is now a leading player in the push for change. If the world is to bring down temperatures, leaders have to follow the example.