WASHINGTON -- A group promoting skepticism over widely-accredited climate change science has a web of connections to influential oil giant Exxon-Mobil, Raw Story has found.

The organization is called the Nongovernmental International Panel on Climate Change (NIPCC), apparently named after the UN coalition International Panel on Climate Change (IPCC). An investigation into the group reveals its numerous links to Exxon-Mobil, a vehement opponent of climate legislation and notorious among scientists for funding global warming skeptics.

"Exxon-Mobil essentially funds people to lie," Joseph Romm, lauded climate expert and author of the blog Climate Progress, told Raw Story. "It's important for people to understand that they pay off the overwhelming majority of groups in the area of junk science."

The NIPCC's signature report, "Climate Change Reconsidered," disputes the notion that global warming is human-caused, insisting in its policy summary that "Nature, not human activity, rules the planet." Many of its assertions have been challenged by, among others, the scientists' blog RealClimate.

The report was released and promoted this summer by the Heartland Institute, a think tank that claims to support "common-sense environmentalism" as opposed to "more extreme environmental activism." It alleges that "Global warming is a prime example of the alarmism that characterizes much of the environmental movement."

"To call global warming a hoax is to question every scientific journal, every scientific academy, and buy into the most extreme conspiracy theories," Romm said.

Heartland has received at least $676,500 from Exxon-Mobil since 1998, the year Exxon launched a campaign to oppose the Kyoto Treaty, according to official documents of the two groups that have been compiled and reproduced by the website ExxonSecrets.org. Also, the institute's self-described Government Relations Adviser Walter F. Buchholtz has been a lobbyist for Exxon-Mobil, the Washington Post reported in 2004.

The study's two principal authors and NIPCC leaders S Fred Singer and Craig D Idso are both associated with various organizations that have gotten generous funding from Exxon-Mobil.

Singer has researched and published for the Cato Institute, which has accepted $125,000 in grants from Exxon-Mobil since 1998. Other professional affiliations include the National Center for Policy Analysis, Frontiers of Freedom, and American Council on Science and Health -- which have accepted contributions of $540,000, $1.27 million and $150,000, respectively, from Exxon.

Although some praise him as a hero, Singer has been slammed by many fellow climate scientists as "a fraud, a charlatan and a showman" for his unorthodox views and research.

His co-author Idso is founder, board chairman and former president of the Center for the Study of Carbon Dioxide and Global Change, whose mission statement is to "separate reality from rhetoric in the emotionally-charged debate that swirls around the subject of carbon dioxide and global change." The organization has taken $100,000 in funding from Exxon since 1998, according to the oil company's reports.

Idso is also affiliated with the George Marshall Institute, which has reportedly won $840,000 from Exxon.

Exxon-Mobil has spent more money lobbying Congress in the last two years than any enterprise other than the Chamber of Commerce, dishing out $29 million in 2008 and over $20 million so far in 2009 to legislators. It's among the top 10 biggest spenders of lobbying cash since 1998, according to the Center for Responsive Politics.

"Exxon has waged certainly the biggest, most concerted, and most extreme disinformation campaign on this issue," Romm told Raw Story. "The trouble is they don't have to win the argument -- all they have to do is blow smoke and cast doubt, and they've accomplished their end."

In a recent incident, hackers exposed private emails exchanged between climate scientists. Some said the revealed information didn't add up to a conspiracy, while others declared it definitive proof that anthropogenic global warming is made-up.

The Senate will soon take up the mantle on climate bill that the House narrowly passed this summer, and a heated debate is likely to occur in Congress over the nature of the threat and the type of action that needs to be taken.

"I think we're going to pass it, but it's going to be an epic struggle," Romm said.

Republican Sen. Orrin Harch has referenced the NIPCC report, calling it a "Comprehensive scientific answer to the IPCC [sic] Reports." Various blogs, such the conservative Free Republic, have touted this report as evidence that "global warming is not a crisis, and never was."