Scientists and economists have been offered US$10,000 each by a lobby funded by one of the world's largest oil companies to undermine a major climate change report due to be published today.
Letters sent by the American Enterprise Institute (AEI), an ExxonMobil-funded think tank with close links to the Bush administration, offered the payments for writing articles that emphasized the shortcomings of a report from the UN's Intergovernmental Panel on Climate Change (IPCC).
Travel expenses and additional payments were also offered.
The UN report was written by international experts and is widely regarded as the most comprehensive review yet of climate change science. It will underpin international negotiations on new emissions targets to succeed the Kyoto agreement, the first phase of which expires in 2012.
World governments were given a draft last year and invited to comment.
The AEI has received more than US$1.6 million from ExxonMobil and more than 20 of its staff have worked as consultants to the Bush administration. Lee Raymond, a former head of ExxonMobil, is the vice chairman of AEI's board of trustees.
The letters, sent to scientists in the US and elsewhere, attack the UN's panel as "resistant to reasonable criticism and dissent and prone to summary conclusions that are poorly supported by the analytical work" and ask for essays that "thoughtfully explore the limitations of climate model outputs."
Climate scientists said the move was an attempt to cast doubt over the "overwhelming scientific evidence" on global warming.
"It's a desperate attempt by an organization who wants to distort science for their own political aims," David Viner of the Climatic Research Unit at the University of East Anglia said.
The letters were sent by Kenneth Green, a visiting scholar at AEI, who confirmed that the organization had approached scientists, economists and policy analysts to write articles for a review of the IPCC report.
"Right now, the whole debate is polarized," he ssaid. "One group says that anyone with any doubts whatsoever are deniers and the other group is saying that anyone who wants to take action is alarmist. We don't think that approach has a lot of utility for policy."
One US scientist turned down the offer, citing fears that the report could easily be misused for political gain.