BackgroundWarming of the climate system is unequivocal, and scientists are more than 90% certain most of it is caused by increasing concentrations of greenhouse gases produced by human activities such as deforestation and burning fossil fuels. These findings are recognized by the national science academies of all the major industrialized countries.
Despite scientific consensus, allegations have been made that scientists and institutions involved in global warming research are part of a global scientific conspiracy. There have been allegations of malpractice, most notably the Climatic Research Unit email controversy. Eight committees investigated these allegations and published reports, each finding no evidence of fraud or scientific misconduct. The Muir Russell report stated, however, "We do find that there has been a consistent pattern of failing to display the proper degree of openness, both on the part of CRU scientists and on the part of the UEA." The scientific consensus that global warming is occurring as a result of human activity remained unchanged at the end of the investigations.
Sample claimsIn a speech given to the US Senate Committee on the Environment and Public Works on July 28, 2003, entitled "The Science of Climate Change", Senator James Inhofe (Republican, for Oklahoma) concluded by asking the following question: "With all of the hysteria, all of the fear, all of the phony science, could it be that man-made global warming is the greatest hoax ever perpetrated on the American people?" He further stated, "some parts of the IPCC process resembled a Soviet-style trial, in which the facts are predetermined, and ideological purity trumps technical and scientific rigor." Inhofe has suggested that supporters of the Kyoto Protocol such as Jacques Chirac are aiming at global governance.
A Washington Post article describing the views of global warming skeptics describes retired hurricane researcher William M. Gray as having "his own conspiracy theory," saying, "He has made a list of 15 reasons for the global warming hysteria. The list includes the need to come up with an enemy after the end of the Cold War, and the desire among scientists, government leaders and environmentalists to find a political cause that would enable them to 'organize, propagandize, force conformity and exercise political influence. Big world government could best lead (and control) us to a better world!'" In this article, Gray also cites the ascendancy of Al Gore to the vice presidency as the start of Gray's own problems with federal funding. According to Gray, the National Oceanic and Atmospheric Administration stopped giving him research grants, and so did NASA.
Commenting on criticism of the Lavoisier Group by Clive Hamilton, the Cooler Heads Coalition notes that "Hamilton accuses the Lavoisier Group of painting the UN's global warming negotiations as "an elaborate conspiracy in which hundreds of climate scientists have twisted their results to support the climate change theory in order to protect their research funding" and adds, "Sounds plausible to us."
MotivesThose who claim global warming has been falsely promoted have alleged various nefarious motives, including:
- A desire on the part of the United Nations and its supporters to promote a system of world government or global governance.
- A desire on the part of climate science researchers to attract financial support
- What Melanie Phillips described as "yet another variation of left-wing, anti-American, anti-west ideology which goes hand in hand with anti-globalisation."
- A desire on the part of conservative political leaders including Margaret Thatcher, and Helmut Kohl to promote nuclear power while attracting the political support of Green groups
- A desire on the part of leftwing political leaders to promote socialism:
- Czech President Václav Klaus said that "This ideology preaches earth and nature and under the slogans of their protection – similarly to the old Marxists – wants to replace the free and spontaneous evolution of mankind by a sort of central, now global, planning of the whole world"
- Nick Minchin, Australian former leader of the Opposition in the Senate stated on the ABC program 4 Corners that "For the extreme left it [climate change] provides the opportunity to do what they've always wanted to do, to sort of de-industrialise the western world. You know the collapse of communism was a disaster for the left, and the, and really they embraced environmentalism as their new religion." 
- According to the 1993 book Science under Siege by Michael Fumento, former US Senator Timothy Wirth, (D-Colo) said that "We've got to ride the global warming issue. Even if the theory of global warming is wrong, we will be doing the right thing – in terms of economic policy and environmental policy.."
CriticismSteve Connor links the terms "hoax" and "conspiracy," saying, "Reading through the technical summary of this draft (IPCC) report, it is clear that no one could go away with the impression that climate change is some conspiratorial hoax by the science establishment, as some would have us believe."
The documentary The Great Global Warming Swindle received much criticism. George Monbiot described it as "the same old conspiracy theory that we’ve been hearing from the denial industry for the past ten years". Similarly, in response to James Delingpole, Monbiot stated that his Spectator article was "the usual conspiracy theories [...] working to suppress the truth, which presumably now includes virtually the entire scientific community and everyone from Shell to Greenpeace and The Sun to Science."
Former UK Secretary of State for Environment, Farming and Rural Affairs, David Miliband presented a rebuttal of the main points of the film and stated "There will always be people with conspiracy theories trying to do down the scientific consensus, and that is part of scientific and democratic debate, but the science of climate change looks like fact to me." John Houghton, previously co-Chair of the IPCC, said, "The most prominent person in the programme was Lord Lawson, former Chancellor of the Exchequer who is not a scientist and who shows little knowledge of the science but who is party to the creation of a conspiracy theory that questions the motives and integrity of the world scientific community, especially as represented by the Intergovernmental Panel on Climate Change (IPCC).
National Geographic fact checked 6 persistent scientific conspiracy theories. Regarding the persistent belief in a global warming hoax they note that the Earth is continuing to warm and the rate of warming is increasing as documented in numerous scientific studies. The rise in global temperature and its rate of increase coincides with the rise of greenhouse gases in the atmosphere due to human activity. Moreover, global warming is causing Arctic sea ice to thaw at historic rates, many species of plants are blooming earlier than expected, and the migration routes of many birds, fish, mammals, and insects are changing.
FundingThere is evidence that some of those alleging such conspiracies are part of well-funded misinformation campaigns designed to manufacture controversy, undermine the scientific consensus on climate change and downplay the projected effects of global warming. Individuals and organisations kept the global warming debate alive long after most scientists had reached their conclusions. These doubts have influenced policymakers in both Canada and the US, and have helped to form government policies.
Since the late 1980s, this well-coordinated, well-funded campaign by contrarian scientists, free-market think tanks and industry has created a paralyzing fog of doubt around climate change. Through advertisements, op-eds, lobbying and media attention, greenhouse doubters (they hate being called deniers) argued first that the world is not warming; measurements indicating otherwise are flawed, they said. Then they claimed that any warming is natural, not caused by human activities. Now they contend that the looming warming will be minuscule and harmless. "They patterned what they did after the tobacco industry," says former senator Tim Wirth, who spearheaded environmental issues as an under secretary of State in the Clinton administration. "Both figured, sow enough doubt, call the science uncertain and in dispute. That's had a huge impact on both the public and Congress."Greenpeace presented evidence of the energy industry funding climate change denial in their 'Exxon Secrets' project. An analysis conducted by The Carbon Brief in 2011 found that 9 out of 10 of the most prolific authors who cast doubt on climate change or speak against it have ties to ExxonMobil. Greenpeace have said that Koch industries invested more than US$50 million in the past 50 years on spreading doubts about climate change. ExxonMobil announced in 2008 that it would cut its funding to many of the groups that "divert attention" from the need to find new sources of clean energy, although it continues to fund over "two dozen other organisations who question the science of global warming or attack policies to solve the crisis." A survey carried out by the UK Royal Society found that in 2005 ExxonMobil distributed US$2.9 million to 39 groups that "misrepresented the science of climate change by outright denial of the evidence".
Former United States Secretary of the Interior Bruce Babbitt stated on the Diane Rehm Show (WAMU-FM, July 21, 1997):
It's an unhappy fact that the oil companies and the coal companies in the United States have joined in a conspiracy to hire pseudo scientists to deny the facts... the energy companies need to be called to account because what they are doing is un-American in the most basic sense. They are compromising our future by misrepresenting the facts by suborning scientists onto their payrolls and attempting to mislead the American people.
Fictional representationsThe novel State of Fear by Michael Crichton, published in December 2004, describes a conspiracy by scientists and others to create public panic about global warming. The novel includes 20 pages of footnotes, described by Crichton as providing a factual basis for the non-plotline elements of the story. In a Senate speech on 4 January 2005, Inhofe mistakenly described Crichton as a "scientist", and said the book's fictional depiction of environmental organizations primarily "focused on raising money, principally by scaring potential contributors with bogus scientific claims and predictions of a global apocalypse" was an example of "art imitating life."
In a piece headed Crichton's conspiracy theory, Harold Evans described Crichton's theory as being "in the paranoid political style identified by the renowned historian Richard Hofstadter," and went on to suggest that "if you happen to be in the market for a conspiracy theory today, there's a rather more credible one documented by the pressure group Greenpeace," namely the funding by ExxonMobil of groups opposed to the theory of global warming.
- Merchants of Doubt - Analysis of denialist movements in America by Erik M. Conway and Naomi Oreskes
- Global warming controversy
- "Revisiting the global warming hoax".
- "Warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice and rising global average sea level." IPCC, Synthesis Report, Section 1.1: Observations of climate change, in IPCC AR4 SYR 2007.
- "Three different approaches are used to describe uncertainties each with a distinct form of language. [...] Where uncertainty in specific outcomes is assessed using expert judgment and statistical analysis of a body of evidence (e.g. observations or model results), then the following likelihood ranges are used to express the assessed probability of occurrence: virtually certain >99%; extremely likely >95%; very likely >90%..." IPCC, Synthesis Report, Treatment of Uncertainty, in IPCC AR4 SYR 2007.
- IPCC, Synthesis Report, Section 2.4: Attribution of climate change, in IPCC AR4 SYR 2007.
- [Notes-SciPanel] America's Climate Choices: Panel on Advancing the Science of Climate Change; National Research Council (2010). Advancing the Science of Climate Change. Washington, D.C.: The National Academies Press. ISBN 0-309-14588-0. "(p1) ... there is a strong, credible body of evidence, based on multiple lines of research, documenting that climate is changing and that these changes are in large part caused by human activities. While much remains to be learned, the core phenomenon, scientific questions, and hypotheses have been examined thoroughly and have stood firm in the face of serious scientific debate and careful evaluation of alternative explanations. * * * (p21-22) Some scientific conclusions or theories have been so thoroughly examined and tested, and supported by so many independent observations and results, that their likelihood of subsequently being found to be wrong is vanishingly small. Such conclusions and theories are then regarded as settled facts. This is the case for the conclusions that the Earth system is warming and that much of this warming is very likely due to human activities."
- [Notes-SciAcademy Statement] "Joint Science Academies' Statement" (PDF). Retrieved 2010-08-09.
- Six of the major investigations covered by secondary sources include: 1233/uk-climategate-inquiry-largely-clears.html House of Commons Science and Technology Committee (UK); Independent Climate Change Review (UK); International Science Assessment Panel (UK); Pennsylvania State University (US); United States Environmental Protection Agency (US); Department of Commerce (US).
- Jonsson, Patrik. "Climate scientists exonerated in 'climategate' but public trust damaged". Christian Science Monitor, 7 July 2010. p. 2. Retrieved 17 Aug. 2011
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- Biello, David (Feb., 2010). "Negating 'Climategate'". Scientific American. (302):2. 16. ISSN 00368733. "In fact, nothing in the stolen material undermines the scientific consensus that climate change is happening and that humans are to blame"; See also: Lubchenco, Jane (2 December 2009) House Select Committee on Energy Independence and Global Warming (House Select Committee). "The Administration's View on the State of Climate Science". House Hearing, 111 Congress. U.S. Government Printing Office. "...the e-mails really do nothing to undermine the very strong scientific consensus and the independent scientific analyses of thousands of scientists around the world that tell us that the Earth is warming and that the warming is largely a result of human activities." As quoted in the report published by Office of Inspector General.
- James M. Inhofe - U.S. Senator - Oklahoma
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