Speaker after speaker at a major climate change conference yesterday warned of a looming catastrophe. But they did not think much was going to be done about it at global warming negotiations later this month in Cancun, Mexico. In one of the largest gatherings of climate experts in Hong Kong, many taking part said urgent and co-ordinated steps needed to be taken by world governments to halt the accelerating effects of climate change. But most were critical of the lack of progress made since the UN's climate summit in Copenhagen in December. The international experts were speaking at the start of the four-day Climate Dialogue run by the independent think tank Civic Exchange at the Hong Kong Convention and Exhibition Centre. 'It is good to talk but I am sceptical that we will see significant progress in Cancun,' said Professor David Drewry, a British environmental scientist with special interest in the polar region. 'I hope they can have the agenda shaped in order to get a better road map to our destination,' said Drewry who sat on the United Nations' Intergovernmental Panel on Climate Change. Painting a gloomy picture of the future for the Arctic, he warned of a melting ice sheet, at a rate of 40,100 square kilometres a year, and the potential catastrophe resulting from the loss of methane-rich permafrost - soil or rocks at below zero degrees Celsius all year round - in Siberia. James Hansen, a Nasa scientist who has been dubbed the 'godfather of global warming', said of the Cancun summit: 'There is no cause of high expectation.' Hansen said nothing much was achieved in the Copenhagen summit because it was heading in the wrong direction of cap and trade which he suspected would only serve the fossil fuel industry. 'It is much better to have a year or two of delay to get started on a more effective approach,' he said. Hansen advocates drastically raising the price of fossil fuels to encourage a switch to alternative energy and to phase out the use of coal. Sharing his anxiety was Will Steffen, executive director of the Climate Change Institute at the Australian National University, who drew the conference audience's attention to the threat to biodiversity from global warming. 'We are running out of time,' he said. Species were disappearing at a much faster rate than before but its impact on the planet was not known, he said. The loss meant humans would lose significant sources of food and medicine as well as the ability to stabilise climate through the storage of carbon in organic species. Martin Lees, former secretary general of global think tank Club of Rome in Switzerland, said people needed to be realistic. 'It has taken 200 years to create this massive problem and we can't expect to salvage [it] in a few months,' he said, adding Cancun should be seen as one step on the road to global consensus. Dr Hu Tao, co-ordinator of the UN-China Climate Change Partnership Programme, warned that a Republican-controlled Congress after the midterm elections in the US could stall climate talks. 'If the Republicans take control, it will be even harder to push legislation for climate change,' he said. 'Without the US, the negotiations will be rocky.'