source: www.cnn.com

LONDON, England (AP) -- Science academies of the G-8 countries joined Tuesday in a call for prompt action to reduce greenhouse gas emissions and warning that delays will be costly.

Lord May, president of Britain's Royal Society, said in releasing the statement that U.S. President George W. Bush's policy on climate change was "misguided" and ignored scientific evidence.

The statement published by the science academies of Britain, France, Russia, Germany, the U.S., Japan, Italy and Canada, along with those of Brazil, China and India, called on G-8 countries to "identify cost-effective steps that can be taken now to contribute to substantial and long-term reductions in net global greenhouse gas emissions."

The statement called on the G-8 nations to "recognize that delayed action will increase the risk of adverse environmental effects and will likely incur a greater cost."

The statement was released as British Prime Minister Tony Blair was meeting with Bush in Washington. Blair has made action on climate change, along with aid to Africa, his priorities for the July G-8 summit in Gleneagles, Scotland.

"It is clear that world leaders, including the G-8, can no longer use uncertainty about aspects of climate change as an excuse for not taking urgent action to cut greenhouse gas emissions," Lord May said.

He noted that the statement was endorsed by science academies of Brazil, China and India -- nations "who are among the largest emitters of greenhouse gases in the developing world."

"The current U.S. policy on climate change is misguided," May added.

"The Bush administration has consistently refused to accept the advice of the U.S. National Academy of Sciences. The NAS concluded in 1992 that, 'Despite the great uncertainties, greenhouse warming is a potential threat sufficient to justify action now,' by reducing emissions of greenhouse gases.

"Getting the U.S. onboard is critical because of the sheer amount of greenhouse gas emissions they are responsible for. For example, the Royal Society calculated that the 13 percent rise in greenhouse gas emissions from the U.S. between 1990 and 2002 is already bigger than the overall cut achieved if all the other parties to the Kyoto Protocol reach their targets."

The statement signed by the academies said evidence of global warming included "direct measurements of rising surface air temperatures and subsurface ocean temperatures and from phenomena such as increases in average global sea levels, retreating glaciers, and changes to many physical and biological systems."

The statement called on G-8 leaders and others to: