There is an undoubted air of optimism in the Danish capital.The reason for the calm is because global warming talks may well result in a deal, according to the head of the UN’s climate change panel. Although the world’s biggest polluters are coming to Copenhagen with no promises to cut greenhouse gas emissions, Yvo De Boer believes much progress will be made. “I believe that negotiators now have the clearest signal ever from world leaders to graft a solid set of proposals to implement rapid action,” he said. “Never, in the 17 years of climate change negotiations, have so many different nations made so many firm pledges together. Almost every day now, countries announce new targets or plans to cut emissions. It’s simply unprecendented,” de Boer added. With global temperatures expected to go up by 3.5 degrees celsius by the century’s end, delegates are likely to set a target, allowing temperatures to rise by no more than 2 degrees. That objective has been described by some activists as a good start to curb global warming. But many developing countries say it is extremely ambitious. They want rich nations who have been burning fossil fuels since the Industrial Revolution to cut their emissions first; and then come up with at least 8 billion of euros a year in aid to help the poor.