What's Copenhagen?

The capital of Denmark, but you knew that. Commentators are billing the international negotiations in Copenhagen this December (officially known as COP15) as "the most important meeting mankind has ever had".

COP15 is the culmination of the United Nations Framework Convention on Climate Change (UNFCCC) process, and it is supposed to produce a binding global agreement to reduce greenhouse gas emissions by enough to prevent 'dangerous anthropogenic interference' in the climate.

In practice, most countries agree that this means limiting global temperature rise to below 2˚C above pre-industrial temperatures. Above 2 degrees, it is believed that frightening feedback mechanisms in the climate system will kick in, causing warming to accelerate to a runaway pace that humanity will no longer be able to prevent by simply reducing our own greenhouse gas emissions. Pretty near every country in the world has signed up to the UNFCCC - which is a good start.

The UNFCCC's greatest achievement to date has been the Kyoto Protocol, which set binding targets for 37 industrialized countries and the European community for reducing greenhouse gas (GHG) emissions. These targets amount to an average of five per cent cuts against 1990 levels over the five-year period 2008-2012. What happens after 2012 is what must be decided at COP15 in Copenhagen this year.

Many scientists now believe that it is too late to achieve the primary UNFCCC goal. As Professor John Holdren, now President Obama's science adviser, put it way back in 2006: "We have already passed the stage of dangerous climate change. The task now is to prevent catastrophic climate change."

Unfortunately the increasingly grim news from the scientific community has not meant that the world's political leaders have knuckled down to work harder on reducing emissions. Far from it; worldwide emissions have been rising faster than even the worst-case scenarios predicted by the global authority on climate change, the IPCC. Meanwhile, we are almost no closer to reaching a deal at Copenhagen than we were 4 years ago when Kyoto came into force. 

At present, the very highest aspirations of any rich nation at COP15 would, if realised in full, give us a 50% chance of avoiding crossing the 2˚C threshold to runaway warming; yet we are very unlikely to achieve even this best-case scenario at Copenhagen.

Most observers agree that the outcome at Copenhagen - and hence, perhaps, the future of civilization - will ultimately be determined by what the USA and China can manage to commit to between them. But the truth is every nation has a crucial role to play in the negotiations, from the powerhouses of the G8 richest economies to the poor, low-lying countries of AOSIS, the Alliance of Small Island States. Nothing less than a comprehensive global deal that is as strong as the science demands will do. All of humanity must agree a way to work together to avert this disaster - or else.

The international politics of climate change, and the relative positions of the world's nations - both with regard to one another and to the absolute targets dictated by the climate science - are fiendishly difficult to follow and understand. Even the delegations themselves can have a hard time keeping up.

The Copenhagen Sprint is a simplified graphic representation of where different countries stand in the climate change stakes, most particularly in the international negotiations leading up to COP15. We hope you find it helpful in getting your head around the mess we're all in, and the (lack of) progress of our politicians in making plans to get us out of it.

It's important to remember that the Sprint metaphor is flawed in one crucial respect; this is not really a race that anybody can win on their own. Getting into the green 'safety' area beyond the finish line does not really mean that country is going to be safe, only that they themselves have taken the necessary steps to achieve climate safety.

Nobody wins until we're all over the finish line.

To get up to date information and more detail on the preparations and background for COP15, visit the official COP15 website. For a quick run-down of some of the key questions and issues, see the Guardian's Copenhagen Q&A. To closely track the Lead Climate Negotiators from each nation, check out the inspired www.adoptanegotiator.org.