Global Warming / Climate Change Hoax

Overview

The climate change hoax conspiracy theory is the claim that anthropogenic (human-caused) global warming is a manufactured crisis fabricated or grossly exaggerated by corrupt scientists, globalist institutions, and left-leaning governments. Proponents allege the true motive behind climate science is to justify carbon taxes, wealth redistribution, expanded government control, and the dismantling of industrial economies. In some versions, the conspiracy encompasses thousands of researchers across dozens of countries, all coordinating to falsify temperature records, suppress dissent, and maintain a lucrative flow of government research grants.

The theory is classified as debunked. The scientific evidence for human-caused climate change is supported by an overwhelming consensus of climate scientists — independently confirmed at between 97% and 99.9% agreement — as well as every major national academy of science on Earth, NASA, NOAA, the European Space Agency, and the Intergovernmental Panel on Climate Change (IPCC). Multiple lines of independent physical evidence, including satellite measurements, ocean heat content, ice core records, and direct atmospheric CO2 monitoring, all converge on the same conclusion. Ironically, internal documents have revealed that the fossil fuel industry’s own scientists confirmed the reality of human-caused warming as early as the 1970s, even as their parent companies funded public doubt campaigns for decades.

While legitimate scientific debate continues about specific climate sensitivities, feedback mechanisms, and the precise pace of future warming, the core proposition that the Earth is warming due to greenhouse gas emissions from human activity is not a matter of serious scientific dispute.

Origins & History

The Tobacco Playbook

The modern climate denial movement did not emerge in a vacuum. Its organizational strategies, rhetorical techniques, and in some cases its actual personnel were drawn directly from the tobacco industry’s decades-long campaign to cast doubt on the link between smoking and lung cancer. Historians of science Naomi Oreskes and Erik M. Conway documented this lineage in their 2010 book Merchants of Doubt, showing how a small network of Cold War-era physicists — including Frederick Seitz, Fred Singer, and William Nierenberg — moved from defending tobacco to defending fossil fuels using the same core strategy: manufacturing uncertainty.

The tobacco industry had discovered in the 1960s that it did not need to prove cigarettes were safe. It only needed to maintain the appearance of a scientific debate. An infamous 1969 memo from a Brown & Williamson executive stated: “Doubt is our product, since it is the best means of competing with the ‘body of fact’ that exists in the mind of the general public.” This approach — funding sympathetic researchers, creating front organizations with scientific-sounding names, attacking mainstream scientists, and demanding impossible standards of proof — became the template for climate denial.

Fossil Fuel Funding and Organized Denial

As scientific understanding of the greenhouse effect solidified through the 1980s, and as political momentum built toward emissions regulations, the fossil fuel industry began organizing resistance. The Global Climate Coalition (GCC), founded in 1989 by a consortium of major oil, coal, automotive, and chemical companies, became one of the earliest and most influential industry groups dedicated to opposing climate action. Internal GCC documents later revealed that the organization’s own scientific advisors had told its members that “the scientific basis for the Greenhouse Effect and the potential impact of human emissions of greenhouse gases such as CO2 on climate is well established and cannot be denied,” yet the group publicly argued the science was too uncertain to warrant regulation.

Through the 1990s and 2000s, fossil fuel companies and allied foundations channeled hundreds of millions of dollars into a network of think tanks, front groups, and media campaigns. Key nodes in this network included the Heartland Institute, the George C. Marshall Institute, the Competitive Enterprise Institute, the American Enterprise Institute, and Americans for Prosperity. Koch Industries founders Charles and David Koch became particularly significant funders, contributing an estimated $145 million to groups promoting climate skepticism between 1997 and 2018, according to a Greenpeace analysis of tax filings.

These organizations produced reports mimicking the style of peer-reviewed research, sponsored conferences designed to resemble scientific meetings, cultivated a roster of credentialed skeptics willing to appear in media, and lobbied lawmakers aggressively. Senator James Inhofe of Oklahoma, who famously called climate change “the greatest hoax ever perpetrated on the American people” on the Senate floor in 2003, received substantial campaign contributions from the fossil fuel industry throughout his career.

Climategate and Its Aftermath

In November 2009, hackers breached the email server of the Climatic Research Unit (CRU) at the University of East Anglia in the United Kingdom, releasing thousands of private emails and documents. Climate skeptics seized on selected passages — particularly a reference to a “trick” to “hide the decline” in a 1999 email from CRU director Phil Jones — as proof that scientists were manipulating data. The incident, dubbed “Climategate” by skeptic blogger James Delingpole, generated enormous media coverage and became the single most prominent piece of alleged evidence in the climate hoax narrative.

The phrase “hide the decline” referred to a well-known and openly discussed technical issue in dendroclimatology (the use of tree-ring data to reconstruct past temperatures), where certain tree-ring records diverge from instrumental temperature measurements after approximately 1960. The “trick” was a standard methodological approach — published in peer-reviewed literature — of splicing instrumental temperature data onto the tree-ring record where the latter was known to be unreliable. None of this was secret, and the divergence problem had been discussed extensively in published scientific papers.

Nine independent investigations subsequently examined the Climategate emails, including inquiries conducted by the U.K. House of Commons Science and Technology Committee, the Independent Climate Change E-mails Review (the Muir Russell inquiry), the University of East Anglia’s Scientific Assessment Panel (the Oxburgh inquiry), Penn State University, the U.S. Environmental Protection Agency, NOAA, and the National Science Foundation’s Office of Inspector General. Every single investigation cleared the scientists of fraud, data manipulation, and scientific misconduct. Several reports did recommend improvements in data transparency and freedom-of-information compliance, but none found any evidence that the scientific conclusions about climate change were compromised.

Key Claims

Proponents of the climate change hoax theory advance several interrelated claims:

• Scientific fraud and data manipulation — Temperature records have been systematically altered or “adjusted” by government agencies to show warming that does not exist. Proponents often point to periodic corrections and homogenization of weather station data as evidence of tampering, though these adjustments are standard quality-control procedures applied transparently and with documented methodology.

• Funding bias and grant corruption — Scientists fabricate or exaggerate climate findings in order to secure government research grants. This claim implies that tens of thousands of researchers across more than 100 countries are independently committing fraud for relatively modest academic salaries, while simultaneously ignoring far more lucrative offers available from the fossil fuel industry.

• Natural climate cycles — Current warming is simply part of natural climate variability caused by solar activity, volcanic eruptions, ocean oscillations, or orbital cycles. While all of these factors do influence climate, peer-reviewed research has shown that natural factors alone cannot account for observed warming since the mid-20th century, and that solar output has been slightly declining since the 1980s even as temperatures have risen sharply.

• The global temperature record is unreliable — Weather stations are poorly sited, affected by urban heat islands, or too sparse to provide accurate global measurements. In reality, multiple independent temperature datasets — maintained by NASA GISS, NOAA, the UK Met Office/CRU, the Japanese Meteorological Agency, and the Berkeley Earth project (the last of which was initially funded by climate skeptics) — all show consistent warming trends. Satellite measurements from UAH and RSS confirm the surface record.

• Climate models are wrong — Computer models of the climate system are unreliable and have consistently overpredicted warming. In fact, a 2019 study by Hausfather et al. published in Geophysical Research Letters evaluated 17 climate model projections made between 1970 and 2007 and found that 14 of them were consistent with subsequent observations.

• CO2 is beneficial and harmless — Carbon dioxide is “plant food” and rising levels are greening the planet, not harming it. While increased CO2 can stimulate plant growth under certain conditions, this ignores the broad array of documented harms from climate change, including rising sea levels, ocean acidification, increased frequency and severity of extreme weather events, disruption of agricultural patterns, and ecosystem collapse.

The Scientific Consensus

The scientific consensus on human-caused climate change is one of the most robust in the history of modern science:

• The 97% consensus: A 2013 study by John Cook et al. published in Environmental Research Letters reviewed 11,944 peer-reviewed climate science papers published between 1991 and 2011 and found that among papers expressing a position on causation, 97.1% endorsed the consensus that human activity is causing global warming. A follow-up 2021 study by Mark Lynas et al. examining over 88,000 climate-related papers found the consensus had risen to 99.9% among papers published since 2012.

• The IPCC: The Intergovernmental Panel on Climate Change, established in 1988 by the United Nations Environment Programme and the World Meteorological Organization, synthesizes the work of thousands of scientists from around the world. Its Sixth Assessment Report (2021-2023) stated unequivocally: “It is unequivocal that human influence has warmed the atmosphere, ocean and land.”

• NASA and NOAA: Both agencies maintain extensive climate monitoring programs and have repeatedly affirmed the reality of human-caused warming. NASA’s Goddard Institute for Space Studies maintains one of the primary global temperature records.

• Every major national academy of science: The national academies of science of the United States, United Kingdom, France, Germany, Japan, China, India, Russia, Brazil, Canada, Australia, and dozens of other countries have all issued statements affirming the scientific consensus on human-caused climate change. There is no national academy of science anywhere in the world that disputes it.

• Professional scientific organizations: The American Meteorological Society, the American Geophysical Union, the American Chemical Society, the American Physical Society, the Geological Society of America, the Royal Society, and virtually every relevant professional scientific body in the world has issued statements consistent with the consensus.

For the climate hoax conspiracy to be true, it would require the coordinated deception of tens of thousands of independent researchers working in hundreds of institutions across dozens of countries, all maintained over a period of more than half a century, with no credible whistleblower ever coming forward with evidence of the fraud.

Exxon Knew

One of the most significant developments in understanding the climate denial movement came from investigative reporting that revealed the fossil fuel industry’s own internal knowledge of climate change.

In 2015, investigative journalists at InsideClimate News and the Los Angeles Times independently published groundbreaking reports based on internal ExxonMobil documents showing that the company’s own scientists had confirmed the reality of human-caused global warming as early as 1977. Exxon’s researchers had accurately projected future warming trends, warned company executives about the consequences, and recommended that the company begin planning for a carbon-constrained world.

Instead of acting on this knowledge or disclosing it to the public and shareholders, Exxon embarked on a multi-decade campaign to cast doubt on the very science its own researchers had validated. The company funded think tanks and front groups that promoted climate skepticism, sponsored misleading advertisements, and lobbied against emissions regulations.

A 2023 peer-reviewed study published in Science by Geoffrey Supran, Stefan Rahmstorf, and Naomi Oreskes conducted a quantitative analysis of ExxonMobil’s internal climate projections and found them to be remarkably accurate — in many cases more accurate than some independent academic projections of the same era. The study demonstrated that Exxon’s scientists had skillfully modeled global warming, predicted with precision where temperatures would be decades later, and correctly dismissed the possibility that an ice age was imminent.

Multiple state attorneys general, including those of New York, Massachusetts, and several other states, launched investigations and lawsuits against ExxonMobil and other fossil fuel companies over their climate deception. In 2024, the European Court of Human Rights issued landmark rulings affirming that governments have obligations to protect citizens from climate change, further shifting the legal and political landscape.

Evidence & Debunking

The evidence for human-caused climate change comes from multiple independent lines of inquiry that all converge on the same conclusion:

• Direct atmospheric measurements: The Mauna Loa Observatory in Hawaii has continuously measured atmospheric CO2 since 1958. Concentrations have risen from approximately 315 parts per million (ppm) to over 425 ppm, a level not seen on Earth in at least 800,000 years according to ice core records, and likely not in millions of years.

• Global temperature records: Four independent surface temperature datasets and two satellite-based datasets all show consistent warming of approximately 1.1 to 1.3 degrees Celsius since the pre-industrial era. The 10 warmest years on record have all occurred since 2010.

• Ice core records: Air bubbles trapped in Antarctic and Greenland ice cores provide a record of atmospheric composition stretching back 800,000 years, showing a tight correlation between CO2 levels and temperature, and confirming that current CO2 concentrations are unprecedented in that timeframe.

• Ocean measurements: The oceans have absorbed more than 90% of the excess heat trapped by greenhouse gases. Ocean heat content has risen dramatically, measured by thousands of Argo floats deployed worldwide. Sea levels are rising at an accelerating rate due to thermal expansion and ice sheet melt.

• Isotopic fingerprinting: The carbon isotope ratio (C-13/C-12) of atmospheric CO2 has been declining, which is a signature unique to fossil fuel combustion. This rules out volcanic activity or ocean outgassing as the source of rising CO2.

• The Berkeley Earth Surface Temperature project: Founded in 2010 by physicist Richard Muller, who had expressed skepticism about the temperature record, and partially funded by the Charles G. Koch Foundation, this project conducted an independent re-analysis of global temperature data. Its conclusions confirmed the findings of NASA, NOAA, and the CRU, and Muller publicly stated that the evidence had convinced him human-caused global warming was real.

Climategate: A Detailed Examination

The Climategate affair deserves extended treatment because of its outsized role in public perception. The hack occurred on November 17, 2009, just weeks before the Copenhagen Climate Summit (COP15), and the timing was widely considered deliberate.

The most frequently cited email was sent by Phil Jones on November 16, 1999, and read in part: “I’ve just completed Mike’s Nature trick of adding in the real temps to each series for the last 20 years (i.e. from 1981 onwards) and from 1961 for Keith’s to hide the decline.” Skeptics presented this as a smoking gun admission of fraud. In context, “Mike’s Nature trick” referred to a technique used by Michael Mann in a 1998 paper published in Nature, and “the decline” referred to the well-documented divergence between post-1960 tree-ring proxy data and instrumental temperatures — a known limitation of that particular proxy dataset that had been openly discussed in scientific literature for years.

Other emails showed scientists expressing frustration with freedom-of-information requests, discussing ways to keep skeptic papers out of journals, and making unflattering private remarks. While these passages revealed normal human frustrations and, in some cases, poor judgment regarding transparency, none of the nine subsequent investigations found evidence that the scientific conclusions were affected.

A second batch of emails was released in November 2011, timed to coincide with the Durban Climate Conference. This release similarly failed to produce evidence of fraud.

The lasting impact of Climategate was not scientific but political. Public polling showed a measurable decline in public acceptance of climate science in the immediate aftermath, particularly in the United States and United Kingdom, though acceptance has since recovered and continued to rise. The episode demonstrated the effectiveness of strategic information release in shaping public opinion, regardless of the actual content of the information.

Cultural Impact

The climate change hoax narrative has had profound effects on politics, policy, and public discourse, particularly in the United States and Australia.

In the United States, climate change became one of the most polarized political issues of the 21st century. Acceptance of climate science correlates more strongly with political party affiliation than with education level or scientific literacy, suggesting that the issue has been successfully framed as a matter of political identity rather than empirical evidence. The Republican Party platform shifted from acknowledging climate change and supporting action in the early 2000s to widespread skepticism or outright denial by the 2010s, a transformation driven in significant part by fossil fuel industry lobbying and the rise of the Tea Party movement.

This polarization has had direct policy consequences. The United States withdrew from the Paris Climate Agreement in 2017 under President Donald Trump, who had previously described climate change as a hoax “created by and for the Chinese.” While the U.S. rejoined in 2021 under President Biden, the episodic nature of American climate policy has complicated international efforts to reduce emissions.

In media, climate denial has been amplified through a network of blogs (such as Watts Up With That and Climate Depot, the latter run by political operative Marc Morano), cable news commentary, and social media. The false balance practiced by many mainstream news outlets — presenting “both sides” of a settled scientific question — also contributed to public confusion for years, though most major outlets have shifted toward more accurate framing.

The climate hoax narrative has also spawned numerous subsidiary conspiracy theories, including claims that wind turbines cause cancer, that the shift to renewable energy is a plot by China, that climate scientists are part of a Marxist conspiracy, and that electric vehicles are tools of government surveillance.

Timeline

• 1896 — Swedish chemist Svante Arrhenius publishes the first calculation estimating that doubling atmospheric CO2 would raise global temperatures by approximately 5 degrees Celsius.
• 1958 — Charles David Keeling begins continuous atmospheric CO2 measurements at Mauna Loa Observatory.
• 1965 — A presidential science advisory committee warns President Lyndon B. Johnson that CO2 emissions could cause significant climate change.
• 1977 — Exxon’s own senior scientist James Black warns executives that CO2 from fossil fuels is warming the planet.
• 1988 — NASA scientist James Hansen testifies before Congress that global warming has begun. The IPCC is established.
• 1989 — The Global Climate Coalition is founded by fossil fuel and industrial companies to oppose climate regulation.
• 1997 — The Kyoto Protocol is adopted. The fossil fuel industry intensifies lobbying against ratification.
• 1998 — Michael Mann, Raymond Bradley, and Malcolm Hughes publish the “hockey stick” graph showing dramatic 20th-century warming.
• 2003 — Senator James Inhofe calls climate change “the greatest hoax ever perpetrated on the American people.”
• 2006 — Al Gore releases An Inconvenient Truth, bringing climate change to mainstream public attention.
• 2007 — The IPCC Fourth Assessment Report states with greater than 90% confidence that human activities are causing warming.
• 2009 — Climategate emails are hacked and released weeks before the Copenhagen Climate Summit.
• 2010 — Nine independent investigations clear Climategate scientists of fraud; Richard Muller launches Berkeley Earth project.
• 2012 — Berkeley Earth confirms global warming findings; Muller publicly reverses his skepticism.
• 2013 — Cook et al. publish the 97% consensus study.
• 2015 — InsideClimate News and the Los Angeles Times publish “Exxon Knew” investigations.
• 2015 — The Paris Agreement is adopted by 196 parties at COP21.
• 2017 — The United States announces withdrawal from the Paris Agreement under President Trump.
• 2021 — The IPCC Sixth Assessment Report calls human influence on warming “unequivocal.”
• 2021 — Lynas et al. study finds 99.9% scientific consensus on human-caused climate change.
• 2023 — Supran, Rahmstorf, and Oreskes publish quantitative analysis confirming accuracy of Exxon’s internal climate projections.

Sources & Further Reading

• Oreskes, Naomi, and Erik M. Conway. Merchants of Doubt: How a Handful of Scientists Obscured the Truth on Issues from Tobacco Smoke to Global Warming. Bloomsbury Press, 2010.
• Cook, John, et al. “Quantifying the Consensus on Anthropogenic Global Warming in the Scientific Literature.” Environmental Research Letters 8, no. 2 (2013).
• Lynas, Mark, Benjamin Z. Houlton, and Simon Perry. “Greater Than 99% Consensus on Human Caused Climate Change in the Peer-Reviewed Scientific Literature.” Environmental Research Letters 16, no. 11 (2021).
• Supran, Geoffrey, Stefan Rahmstorf, and Naomi Oreskes. “Assessing ExxonMobil’s Global Warming Projections.” Science 379, no. 6628 (2023).
• Hausfather, Zeke, et al. “Evaluating the Performance of Past Climate Model Projections.” Geophysical Research Letters 47, no. 1 (2020).
• IPCC. Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report. Cambridge University Press, 2021.
• Banerjee, Neela, Lisa Song, and David Hasemyer. “Exxon: The Road Not Taken.” InsideClimate News, 2015.
• Mann, Michael E. The Hockey Stick and the Climate Wars: Dispatches from the Front Lines. Columbia University Press, 2012.
• Brulle, Robert J. “Institutionalizing Delay: Foundation Funding and the Creation of U.S. Climate Change Counter-Movement Organizations.” Climatic Change 122 (2014): 681-694.
• Muir Russell, Sir Ronald, et al. The Independent Climate Change E-mails Review. University of East Anglia, 2010.