Alister Doyle, Reuters 29 May 08;
OSLO (Reuters) - Governments will have to cut greenhouse gases far more deeply than planned to control global warming and high food prices linked to droughts are a wake-up call, four leading scientists said on Thursday.
"We have lost 10 years talking about climate change but not acting on it," the experts, led by Britain's Martin Parry who is a co-chair of a U.N. Climate Panel group on the impacts of climate change, wrote in the journal Nature.
They said there was "false optimism" about easy fixes.
By 2050, global emissions would have to be cut by 80 percent of the 1990 levels -- well beyond the 50 percent target under consideration for a July summit in Japan by the Group of Eight industrial nations.
"We are now probably witnessing the first genuinely global effects of greenhouse gas warming," they wrote of high food prices partly caused by droughts, for instance in major grains producer Australia, and by a drive to produce biofuels on farm land.
"This should serve as a wake-up call," they said. More than 190 nations have agreed to work out a new long-term treaty by the end of 2009 to combat climate change to succeed the U.N.'s Kyoto Protocol.
Cuts in emissions and efforts to adapt to the impacts of a changing climate "will need to be much stronger than currently planned if dangerous global impacts of climate change are to be avoided," they wrote.
Their study showed that even a 50 percent cut in world emissions by 2050, the most stringent goal considered by G8, was too little to avert dangerous impacts such as water shortages and rising seas even with further cuts at the same pace to 2100.
"Limiting impacts to acceptable levels by mid-century and beyond would require an 80 per cent cut in global emissions by 2050," they wrote.
G8 environment ministers meeting in Japan last weekend urged leaders at a summit in July to set a global target of halving greenhouse gases by 2050, a goal favored last year by all G8 nations except the United States and Russia.
President George W. Bush announced a policy last month, however, that will let U.S. emissions keep rising until 2025.
"The picture is much bleaker and I'm much less optimistic than I was," Parry told Reuters. A continued rise in emissions by the United States, the top emitter with China, would make deep cuts by mid-century ever more difficult, he said.
An 80 percent cut in emissions levels would limit a rise in global temperatures to 2 Celsius (3.6 Fahrenheit) above pre-industrial levels, a level viewed by the European Union as a threshold for "dangerous" changes, the study said.
Parry noted that contenders to succeed Bush -- Republican John McCain and Democratic hopefuls Barack Obama and Hillary Clinton -- favored U.S. cuts of 50 percent by 2050. That was too little when developed nations had to lead the way, he said.
The scientists said they were writing their personal opinions. Parry said he would not seek re-election to the U.N.'s Intergovernmental Panel on Climate Change in September so could write more freely.
(Editing by Jon Boyle)
