Xi and Obama have shown leadership on emissions

In the cynical world of politics it is important, just occasionally, to give credit where it is due. The commitments on carbon emissions announced on Wednesday by President Barack Obama of the US and President Xi Jinping of China, supported by the significant diplomacy of Secretary of State John Kerry, are both environmentally substantive and politically influential. Between them, these countries account for 44 per cent of global carbon emissions – a share that is still rising.

The US has promised that by 2025 its emissions will be at least 26 per cent lower than they were two decades earlier. China has pledged that its carbon emissions will peak around 2030 and that carbon-free energy sources will account for 20 per cent of what it consumed by the same year.

This sea change comes just five years after the setbacks of the Copenhagen summit of 2009. In the lead-up to the crucial Paris conference on climate change in December next year, these American and Chinese commitments will make a significant difference to the debate.

China once saw a warming planet as a problem for the west, which created the phenomenon in the first place. Now, as a rising power, it sees that it too has a responsibility to deal with climate change.

The impetus is mainly domestic. In the minds of Chinese people, there is a close correlation between air pollution and global warming – and, like everyone else, the Chinese are demanding clean air to breathe. Mr Xi has grasped this and decided to act.

Some observers have objected that Chinese emissions would peak around 2030 even without the deal, as the country’s growth trajectory passes its apogee. Yet the Beijing announcement states that both sides “intend to continue to work to increase ambition over time”. We should not forget that there are still 12 months to go before Paris. The normal negotiating dynamics, and occasional histrionics, will ensue. Plainly there is more to be done by both China and America.

Not only has China definitively reaffirmed its commitment to a binding legal agreement for 2015. It has also for the first time recognised its mitigation actions “as part of a longer range effort to transition to low carbon economies, mindful of the global commitment” to 2C. This was a carefully negotiated part of the text. It reflects the conclusion among Chinese policy makers that Paris is not an end-point. Instead, they see it as the beginning of a long process of decarbonising the economy to meet an agreed environmental constraint.

The Beijing declaration also puts new pressure on other countries. International attention will now focus on India, which is no more immune from the impact of climate change than China. Adverse effects are already being felt across the subcontinent.

To be fair to Prime Minister Narendra Modi, he has barely been in office for 100 days. He recently established a National Council on Climate Change, which he himself chairs. The challenge over the next 12 months will be to avoid boxing India into a corner. Washington needs to work with New Delhi to secure an outcome at the Paris conference that works both for India and the world.

Both the French President François Hollande and his foreign minister, Laurent Fabius, are already burning the midnight oil in anticipation of the 2015 conference. No government in the world would want that job for all the tea in China.

The obstacles are formidable. Everyone will criticise “the process”. But the Beijing announcement has demonstrated what a cocktail of political imagination and global leadership can produce – particularly if we all put our minds to it. Presidents Obama and Xi have not only raised the stakes for themselves on the road to Paris, they have done so for us all.

The writer, a former Australian prime minister, led his country’s delegation to Copenhagen in 2009