Leading article: We will all pay a price for failure in Durban

It would be reassuring to know dilemmas of global proportions can always count on getting a degree of world attention, but as some 200 leaders assemble today for the climate change conference in Durban, most eyes seem averted from the life-and-death issues up for debate. The US public is preoccupied with forthcoming elections and America's relative decline in the world while Europe is gripped by the euro-zone crisis. Fears of economic meltdown trump concerns about melting ice caps – though the former are surely easier to fix than the latter.

But the stakes in Durban are higher than ever as countries wrestle over ways to halt rising temperatures and, specifically, over renewal of the 1997 Kyoto protocol – a sub-treaty of the 1992 UN framework treaty agreed in Rio – which all countries signed but which only impacted on the old industrialised West and Japan.

Kyoto bound what were then the world's major polluters to cut carbon emissions by 2008-12, working on a baseline of emissions in 1990. At the time, there wasn't much argument about which countries would have to do most to cut emissions. The US was then the world's biggest polluter, producing 25 per cent of C02.

The problem is that since 1997 the world economy has been transformed. In the 1990s China was industrialising fast but few grasped the scale of its coming explosion in economic activity. China's role as a polluter has expanded accordingly. From 1996 to 2007 its carbon emissions doubled and in 2007 it took over from the US as the world's largest polluter. China now is responsible for 24 per cent of C02 emissions while the US is "only" responsible for 16 per cent.

This shift leaves the Kyoto provisions looking out of sync with the new economic reality, as Kyoto did not oblige China or India to do anything to cut emissions, while giving Japan, China's neighbour, tough goals to meet. If China, India and some other fast-growing economies recognised Western complaints about this inherent unfairness as valid, matters in Durban might be easier. But beyond the fact that an agreement to renew Kyoto in December 2012 poses no dilemma for them, they see Western adherence to Kyoto as a gesture of good faith. They also argue that while China may be the biggest polluter today, the reason why the earth's atmosphere is so polluted is because the rich, industrialised West made it so over decades.

There may be logic to this but it gets us nowhere nearer an agreement on keeping climate change within tolerable boundaries, and the old industrialised powers are correct to respond that any new agreement that does not include China is worthless.

Does a way out of this logjam exist? It does not look hopeful. Three signatories to Kyoto, Japan, Russia and Canada, have already said they will not renew the protocol, while the US, which withdrew support under George Bush in 2001, remains outside the process.

The position formulated by Britain in 2010, which is now the common European position, seeks to triangulate the process. The idea is that the West agrees to renew Kyoto, pleasing China and its allies, while in parallel a treaty is negotiated involving everyone. This is the big prize, an all-encompassing treaty that recognises current economic reality. Even in the best-case scenario it cannot be agreed this year but Durban would be counted a success if there was at least an agreement in principle.

The other scenario is, of course, no agreement – everyone goes home and the clock carries on ticking. This would be disastrous. If we are to keep the rise in average temperatures within two degrees above the pre-industrial level, the range that scientists consider the maximum tolerable, emissions must peak by 2020, which means reaching a planetary agreement on emissions some time before that, by 2015 at the latest. Time is short.