The head of the UN's climate body said at the opening of the long-awaited conference in Copenhagen on climate change that 'the clock has ticked down to zero. The time has come to deliver'. "In a show of support, 105 world leaders have said they will attend the talks' closing stages to try to seal a deal after years of bitter debates over how to divide up the burden of emissions curbs and who should pay," The National reported. "On Sunday, the UN climate chief said time was up to agree on the outlines of a tougher climate deal after troubled negotiations have deepened splits between rich and poor nations. " 'I believe that negotiators now have the clearest signal ever from world leaders to draft a solid set of proposals to implement rapid action,' Yvo de Boer told reporters." Reporting on the opening day of the conference, The Guardian said: "Lars Løkke Rasmussen, the prime minister of Denmark, appealed to the 192 countries present to be prepared to compromise to achieve one of the most important agreements that the world would ever make. 'The political resolve to forge a global deal is manifest. Differences can be overcome if the political will is present. I believe it is,' he said. " 'The clock has ticked down to zero. The time has come to deliver. The time has come to reach out to each other,' said Yvo de Boer, the head of the UN's climate body. "Diplomats in the vast Bella conference centre on the edge of the city were warned strongly by Rajendra Pachauri, the chair of the UN's Nobel prize-winning Intergovernmental Panel on Climate Change (IPCC), that unless a way was found to limit greenhouse gas emissions that sea ice would entirely disappear, cyclones and hurricanes would become more powerful and many of the world's cities would be drowned by sea level rise by the end of the century." "Fourteen days to seal history's judgment on this generation," the title of a common editorial that appeared in 56 newspapers in 45 countries, was a call to action as 20,000 delegates gathered for the climate summit. The editorial said: "Unless we combine to take decisive action, climate change will ravage our planet, and with it our prosperity and security. The dangers have been becoming apparent for a generation. Now the facts have started to speak: 11 of the past 14 years have been the warmest on record, the Arctic ice-cap is melting and last year's inflamed oil and food prices provide a foretaste of future havoc. In scientific journals the question is no longer whether humans are to blame, but how little time we have got left to limit the damage. Yet so far the world's response has been feeble and half-hearted." Ian Katz, described the process that led to the editorial's publication: "Anyone studying the list of newspapers behind the editorial will quickly spot one glaring gap: the absence of any first-rank US paper. A number of major US titles evinced support for the project, even conceding that they agreed with everything in the editorial, but stopped short of signing up, leaving the admirably independent-minded Miami Herald as the sole representative of the world's second biggest polluter." Meanwhile, The Washington Post reported: "President Barack Obama has been armed with new ammunition for the Copenhagen summit on climate change with an announcement on Monday giving the US administration enhanced authority to regulate carbon dioxide emissions. "A formal ruling issued by the Environmental Protection Agency that carbon dioxide and five other gases were a danger to human health will allow the administration to use the Clean Air Act to crack down on emissions from industrial plants. "But the decision to use regulation rather than legislation to cut carbon emissions is politically contentious, with big business and Republicans already protesting the decision as heavy-handed. "Mr Obama, who will travel to Denmark on Friday next week, had hoped Congress would pass a climate change law that would legislate for reductions, but the bill has become mired in the Senate and is not expected to be debated until well into 2010." The New York Times noted: "Just two years ago, a United Nations panel that synthesises the work of hundreds of climatologists around the world called the evidence for global warming 'unequivocal'. "But as representatives of about 200 nations converge in Copenhagen on Monday to begin talks on a new international climate accord, they do so against a background of renewed attacks on the basic science of climate change. "The debate, set off by the circulation of several thousand files and e-mail messages stolen from one of the world's foremost climate research institutes, has led some who oppose limits on greenhouse gas emissions, and at least one influential country, Saudi Arabia, to question the scientific basis for the Copenhagen talks. "The uproar has threatened to complicate a multiyear diplomatic effort already ensnared in difficult political, technical and financial disputes that have caused leaders to abandon hopes of hammering out a binding international climate treaty this year." George Monbiot wrote: "The denial industry, which has no interest in establishing the truth about global warming, insists that these e-mails, which concern three or four scientists and just one or two lines of evidence, destroy the entire canon of climate science. "Even if you were to exclude every line of evidence that could possibly be disputed - the proxy records, the computer models, the complex science of clouds and ocean currents - the evidence for man-made global warming would still be unequivocal. You can see it in the measured temperature record, which goes back to 1850; in the shrinkage of glaciers and the thinning of sea ice; in the responses of wild animals and plants and the rapidly changing crop zones. "No other explanation for these shifts makes sense. Solar cycles have been out of synch with the temperature record for 40 years. The Milankovic cycle, which describes variations in the Earth's orbit, doesn't explain it either. But the warming trend is closely correlated with the accumulation of heat-trapping gases in the atmosphere. The impact of these gases can be demonstrated in the laboratory. To assert that they do not have the same effect in the atmosphere, a novel and radical theory would be required. No such theory exists. The science is not fixed - no science ever is - but it is as firm as science can be. The evidence for man-made global warming remains as strong as the evidence linking smoking to lung cancer or HIV to Aids." The author and environmentalist, Bill McKibben, wrote: "Physics has set an immutable bottom line on life as we know it on this planet. For two years now, we've been aware of just what that bottom line is: the Nasa team headed by James Hansen gave it to us first. Any value for carbon dioxide (CO2) in the atmosphere greater than 350 parts per million is not compatible 'with the planet on which civilization developed and to which life on earth is adapted.' That bottom line won't change: above 350 and, sooner or later, the ice caps melt, sea levels rise, hydrological cycles are thrown off kilter, and so on. "And here's the thing: physics doesn't just impose a bottom line, it imposes a time limit. This is like no other challenge we face because every year we don't deal with it, it gets much, much worse, and then, at a certain point, it becomes insoluble - because, for instance, thawing permafrost in the Arctic releases so much methane into the atmosphere that we're never able to get back into the safe zone. Even if, at that point, the US Congress and the Chinese Communist Party's Central Committee were to ban all cars and power plants, it would be too late."