This is the last day of the Climate talks in Cancun and it doesn’t look as if a deal is likely to get done. The complexity of striking a deal among so many participants with differing points of view is defeating the process and a simpler approach will need to be adopted if progress is to be made in future.

This may be the last chance to put a new climate change deal in place before the Kyoto Climate agreement expires at the end of 2012. But, when that deal was structured in 1997, it was easier to arrive at consensus.

Then, the industrialised countries clearly accounted for the bulk of the world’s CO2 pollution. The US accounted for 25% on its own, and the OECD countries of Europe accounted for a further 20%. The industrialised world as a whole was responsible for three quarters of emissions. So, it was not difficult to sign up to an agreement that everybody should act in accordance with their “common differentiated responsibilities”. This meant that the Industrialised countries agreed to take on legally binding commitments to reduce their emission of greenhouse gasses, and the developing countries agreed that although this was an important topic, they would not have to make any commitments at all.

The story of the failure at the Copenhagen summit last year and the Cancun summit so far, is the story of the developing countries wanting this agreement to be renewed, and the industrialised countries saying that the world has changed, and the developing countries now have to sign up to pledges of their own. The reason for this hardening of attitude amongst the industrialised countries is that now the developing countries are contributing far more to the problem. In 2007 China overtook the US as the world’s biggest polluter. In 2010 the developing nations nearly equalled the emissions of the Industrialised world and they will shortly overtake the developed countries. Small wonder that some industrialised countries led by Japan, are saying that Kyoto cannot be extended unless everybody signs up to some commitments. And small wonder that developing countries, which are beginning to enjoy the fruits of industrialisation, are resisting that call, led by a number of Latin American states.

So, what is to be done? From a negotiating point of view, one problem is clearly that there are over 15,000 delegates in Cancun, representing more than 200 countries. This number of participants in a deal may be possible to manage where there is common ground (as there was at Kyoto in 1997), but it’s virtually impossible to manage where there is such divergence of opinion.

It’s very hard to manage the complexity of such multi-party negotiations, other than by agreeing to anodine communiqués which achieve nothing. So, one answer might be to break the process down into smaller chunks, with trading blocs or regions holding their own negotiations in which climate commitments can be horse-traded in return for (e.g.) trading benefits. No doubt these negotiations would create their own tensions, but they would be simpler to manage than a global process. In terms of climate management local scattered showers are much easier to manage than a perfect storm…….