 After two gloomy UN. reports on global warming, scientists and governments began on Monday looking at how to fight climate change, with green groups saying the world has the means to cut emissions at little cost. "Science certainly provides a lot of compelling reasons for action," Rajendra Pachauri, chairman of the Intergovernmental Panel on Climate Change (IPPC) said as experts from more than 100 nations gathered in Bangkok to debate a raft of solutions. "The IPCC doesn't have any muscle, it has grey matter. The muscle will have to come from somewhere else," he said when asked how its third report of the year to be issued on Friday could be converted into government action. Delegates will wade through 140 pages of nearly 1,000 proposed amendments to the draft 24-page report, which says time for inexpensive fixes is running out because of a surge in greenhouse gas emissions. Major polluters such as United States, China and top oil producer Saudi Arabia are expected to seek to water down the report, wary of language that prescribes targets to cut emissions or threatens their oil and gas industries. The head of U.S. delegation, Harlan Watson, said it was crucial for the report to reflect the best science in tackling global warming. "The U.S. is actively reducing projected emissions growth by increasing energy efficiency and reducing barriers for the wider use of clean energy technologies that also ensure greater energy security and continued economic growth," he said in a statement. The UN. climate panel issued its first report in February, saying it was at least 90 percent certain that mankind was to blame for warming. The second report on April 6 warned of more hunger, droughts, heatwaves and rising seas. Green groups say the time for bickering is over. "The key thing is whatever they decide here, it cannot be ignored anymore that climate change is happening in a big way," said Stephan Singer, head of the WWF's Climate Change Policy Unit. "It's happening much faster. We have more solutions out there than before and it's not as costly as some people want us to believe it is," he added. The report estimates that stabilising greenhouse gas emissions will cost between 0.2 percent and 3.0 percent of world gross domestic product by 2030, depending on the stiffness of curbs on rising emissions of greenhouse gases. Under some scenarios, GDP growth might even get a tiny net spur from less pollution and health damage from burning fossil fuels, blamed as the main cause of warming. The conclusions broadly back those by former World Bank chief economist Nicholas Stern, who estimated last year that costs of acting now to slow warming were about one percent of global output -- and 5 to 20 percent if the world delayed action. More than 1,000 amendments have been proposed to the draft 24-page summary for policymakers. Some countries complain it is hard to understand and too laden with scientific jargon. The report lays out solutions such as capturing and burying emissions from coal-fired power plants, a shift to renewable energies such as solar and wind power, more use of nuclear power, more efficient lighting and insulation of buildings. But it says temperatures will rise by at least 2 to 2.4 Celsius (3.6 - 4.2F) above pre-industrial levels even under the most stringent curbs. The European Union says a 2 C rise is a threshold for "dangerous" changes to the climate system. The more deep and rapid the emissions cuts, the more costly to economies, says the draft report, which gives a range of stabilisation levels of greenhouse gases in the future. By 2030, the costs of letting greenhouse gas concentrations rise to 650 ppmv (parts per million volume) of CO2-equivalent are 0.2 percent of global gross domestic product, it says. Greenhouse gas concentrations are now at about 430 ppmv of carbon dioxide and rising sharply. South African delegate Peter Luckey said any talk of stabilising greenhouse gas concentrations at 650 ppmv "is quite disturbing to us" as too high.