OSLO (Reuters) - A study of a 2003 heatwave in Europe may give Pacific islanders and environmentalists new ammunition for legal cases blaming the United States for global warming, advocates said on Thursday.
Claims linked to climate change could dwarf billion-dollar awards against tobacco companies if U.N. forecasts to 2100 of rising temperatures, higher sea levels, catastrophic storms and droughts turn out to be true, they said.
"This is the kind of evidence that will help those seeking compensation," Peter Roderick, director of the Climate Justice Program which advises plaintiffs, said of a study of Europe's 2003 heatwave published on Wednesday in the journal Nature.
The British-based authors said human activity, especially emissions of heat-trapping gases from fossil fuels, had at least doubled the risks of heatwaves like last year's in which more than 20,000 people died.
The conclusion is a shift from studies saying that everything from more frequent hurricanes to floods could simply be statistical freaks even though they are consistent with U.N. projections of warming caused by a build-up of greenhouse gases.
"One study is not going to create an entire new area of jurisprudence, but this is an important step," Steve Sawyer, climate policy director at Greenpeace, said of the Nature study.
"Like tobacco lawsuits, it may take decades to be successful," he said. U.S. officials dismiss any cases, saying Washington is acting to curb growth of greenhouse gas emissions and aggressively funding research into renewable energy.
Greenpeace is involved in lawsuits accusing the U.S. Export-Import Bank of wrongly funding fossil fuel projects in poor nations and another accusing the U.S. Environmental Protection Agency (news - web sites) of failing to rein in greenhouse gases.
SUE OR BE SWAMPED?
Low-lying Pacific island states including Tuvalu, at risk of disappearing if sea levels rise, are considering suing the United States, the world's top source of greenhouse gases, to force it to do more to curb global warming.
Washington has taken the brunt of legal actions since President Bush (news - web sites) pulled out of the U.N.'s 128-nation Kyoto protocol in 2001, saying its goals for cutting emissions would be too costly and wrongly excluded poor nations.
Writing in Nature, the experts said that the heatwave study still meant huge barriers to any claimants.
"It will almost always be impossible to say that 'but for' greenhouse gases, this event would never have occurred," wrote physicist Myles Allen of Oxford University and senior London lawyer Richard Lord.
"Other legal questions about whether emitters should have foreseen damage, and their fault or negligence, will present formidable hurdles to claimants," they said.
Among other cases, eight U.S. states and New York City filed suit against five U.S. power companies in July, accusing them of stoking climate change. The firms have asked for the case to be dismissed, arguing that climate change is a matter for the president and Congress.
And away from the courts, Inuit hunters argue that melting Arctic ice threatens their livelihood and plan to petition a commission of the Organization of American States to brand climate change a human rights abuse by the United States.