Experts meet on U.N. report but time running out

(Adds opening ceremony, quotes)

By David Fogarty

BANGKOK, April 30 (Reuters) - After two gloomy U.N. reports on global warming, scientists and governments on Monday began looking at how to fight climate change, with green groups saying the world has the means to cut emissions at little cost.

Experts are meeting in Bangkok to review the latest U.N. report, with a raft of solutions to be issued on Friday after review by more than 100 nations.

The draft report warns that time for inexpensive fixes is running out because of a surge in greenhouse gas emissions.

The survey is the third this year by the Intergovernmental Panel on Climate Change (IPCC).

"Science certainly provides a lot of compelling reasons for action," IPCC chairman Rajendra Pachauri told reporters.

When asked how the IPCC could convert the report into government action, he said: "The IPCC doesn't have any muscle, it has grey matter. The muscle will have to come from somewhere else."

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 proscribes targets to cut emissions or threatens their oil and gas industries.

The U.N. 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 by governments is over.

"The key thing is whatever they decide here that it cannot be ignored anymore that climate change is happening in a big way. 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," said Stephan Singer, head of the WWF's Climate Change Policy Unit.

MANY SOLUTIONS

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 -- 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 that 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".

He worried that some governments will try to water down the draft recommendations.

"Our major mandate is to defend the document as much as possible," Luckey, chief director of air quality management in South Africa's Department of Environment Affairs and Tourism. (Additional reporting by Darren Schuettler and Ed Cropley) (Editing by Sonya Hepinstall; Reuters messaging: rm://david.fogarty.reuters.com@reuters.net; email: david.fogarty@reuters.com, telephone: +65 6870 3815))