Sometime towards the end of the Copenhagen climate conference, Michael Zammit Cutajar, a Maltese diplomat and conference chairman, will gather 20 or so people into a back room of the Bella Conference Centre for an all-night session (or two) to do the deal. All the noise and the posturing, the 20,000 delegates, the lobbyists, the dramatic green demonstrators, the 180-page legal negotiating text, will be shut outside.

Those 20 people — representatives of the world’s key climate-change governments — will have in front of them perhaps a ten-page text. They will agree, or not, on greenhouse gas emissions limits for developed countries, financial assistance for developing countries and emissions constraints that developing countries are willing to take on in exchange for that assistance. If they find agreement they will sell it to the wider conference and then to the wider world. It will set our course for at least the decade to come.

What are the chances of success? Of all the negotiations I have been involved with, those on climate have been the hardest to call. This is the biggest piece of international business that mankind has ever done. Huge interests are involved (we are talking about fundamental reform of the world’s trillion-dollar energy sector). Lobbyists, from Exxon to Greenpeace, are stridently present. The range of national interests — from Saudi Arabia’s dependence on hydrocarbons to Vanuatu’s potential submersion — is bewilderingly wide. And because it is so important, the maelstrom of corridor plotting, text chopping, endless reaffirmation of entrenched negotiating positions and rhetoric make it very hard to identify where the centre of gravity might lie.

In the case of Copenhagen the shelving of efforts to finalise a legally binding text demonstrates how complex and fractious things have become. That the negotiation coincides with a world recession limits what rich countries can offer. And the poor world remains obdurate that it will do nothing the rich world won’t pay for. On the other hand, no one wants to take responsibility for failure. The US has come up with its first real offer on emission cuts since its abandonment, a decade ago, of the Kyoto Protocol. Even in India (a benchmark developing country) there is some debate about more flexibility.

So outright failure is unlikely. But it is equally unlikely that Copenhagen will get us right around the climate corner. The probability has to be, at best, an interim deal with lots of work still to do. This is a pity because, behind the fog of negotiation, the political landscape is more positive than it has ever been.

Two key things have changed. First, US public and scientific opinion is much more convinced of the reality of climate change, and the need to deal with it, than was the case at Kyoto. And the US now has an administration ready to take the lead. This doesn’t mean it will be easy to reduce US energy profligacy, but at least the will is now there.

Second, the hitherto refusal of the developing world to contribute to emissions reductions is beginning to fragment. Key players, led by China and Brazil, recognising the potential costs of climate change for themselves as well as the benefits of taking the lead in energy-saving technology, are now looking for ways to constrain their emissions growth. This is a huge step in negotiations that have been dominated by a sterile confrontation between developed and developing blocs. In a world where the annual increase in China’s emissions alone outweighs all of the savings achieved by the Kyoto Protocol, it is a crucial step.

But, while the politics may be moving from red to green, the science tells us that the timing problem is acute. The positive trend is undermined by evangelism winning over objectivity in the scientific debate. The reports of the Intergovernmental Panel on Climate Change read more like exercises in advocacy than sober scientific analysis. This has undermined the credibility of their projections and contributed to the growth of “climate agnosticism”, led here by Nigel Lawson.

Even taking into account the huge uncertainties, the picture painted by the IPCC and others is both persuasive and stark. We have perhaps a couple of decades to reduce global emissions if we are to avoid catastrophic climatic effects.

It is hard to see the negotiating process moving fast enough to turn this round. Its first product, the 1991 Rio Convention, was broken-backed at birth. Its second product, the 1997 Kyoto Protocol, was abandoned by the US and, to the extent it did succeed, only did so because of the Soviet industrial collapse. The process has been bedevilled by green posturing, overoptimistic target setting, US solipsism and Third World militancy. The “Copenhagen Protocol”, if we get there, will reincorporate the US and begin to place downward pressure on the fastest-growing emissions; those from developing countries. But while those emissions may grow more slowly, they will continue to grow. The governments of the poor are not going to let concern about the climate condemn their people to remain poor.

So radical new approaches are going to be needed. Expect, after Copenhagen, much more talk of carbon taxes and tariffs. Expect, too, sharply increased interest in the various “geoengineering” options recently aired by the Royal Society: global afforestation, deliberate plankton growth, “space mirrors”, artificial volcanoes. Wacky (and hideously difficult to agree) as some of these may seem, they may soon be our only way out.

Tony Brenton was a British diplomat from 1975 to 2009, most recently serving as Ambassador to Moscow

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