Climategate proved climate scientists faked data

Climategate proved climate scientists faked data
	FALSE
	"Emails stolen from the University of East Anglia's Climatic Research Unit in 2009 proved that climate scientists manipulated or fabricated data, and that global warming is a hoax."
Domain	Science & Environment
Tactic	False Context; Conspiracy Theory;
Era	Current
First seen	2009
Origin	Publication of hacked emails and documents from the Climatic Research Unit, University of East Anglia, United Kingdom, November 2009
Last reviewed	2026-10-26
	Further reading: books on Science & Environment

In November 2009, weeks before a major United Nations climate summit in Copenhagen, more than a thousand emails and thousands of documents were stolen from the Climatic Research Unit (CRU) at the University of East Anglia in the United Kingdom and posted online. Critics of climate science quoted selected phrases, such as "Mike's Nature trick" and "hide the decline," as proof that scientists had falsified evidence of global warming. The episode, which critics named Climategate, received worldwide coverage. Eight separate investigations in the United Kingdom and the United States examined the scientists' conduct. None found evidence of fraud or scientific misconduct, or that the emails undermined the evidence for human-caused climate change, though several criticized the scientists for a lack of openness and their handling of information requests.

The claim

The claim held that the emails revealed a conspiracy among leading climate scientists to manipulate temperature data, suppress dissenting research and exaggerate global warming, and therefore that the science of climate change could not be trusted.

The emails

The most widely quoted email, sent in 1999 by the CRU's director, Phil Jones, 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... and from 1961 for Keith's to hide the decline."

Read in context, the phrases referred to technical matters:

"Trick" was used in the scientific sense of a clever method, referring to a technique used by the climate scientist Michael Mann in a paper in Nature of combining reconstructed past temperatures with measured temperatures in a graph.
"The decline" referred not to a decline in global temperatures but to a known problem with certain tree-ring records. Tree rings are used to estimate past temperatures, but some tree-ring series from northern regions stopped tracking measured temperatures after about 1960, showing a decline that thermometers did not. This "divergence problem" had been discussed openly in scientific papers. Jones's email described replacing the unreliable recent tree-ring data with actual thermometer measurements in a graph.

Other emails showed scientists expressing frustration with critics, discussing how to respond to papers they considered flawed, and resisting freedom-of-information requests.

How it spread

The emails appeared online on 17 November 2009 and were rapidly publicized by climate-skeptic blogs, then by mainstream news outlets worldwide. The timing, just before the Copenhagen summit in December 2009, magnified their impact. Commentators and politicians in several countries cited them as evidence that climate science was fraudulent. Phil Jones received death threats and temporarily stepped down as director of the CRU while investigations took place.

What the investigations found

Eight inquiries examined the emails and the scientists' work, including:

The UK House of Commons Science and Technology Committee (2010), which found that Jones's reputation and that of the CRU remained intact, while criticizing a culture of withholding information.
The International Science Assessment Panel led by Lord Oxburgh (2010), which found no evidence of deliberate scientific malpractice.
The Independent Climate Change Email Review led by Sir Muir Russell (2010), which found the scientists' "rigour and honesty" were not in doubt, but criticized their lack of openness and their responses to freedom-of-information requests. It also found that a 1999 graph prepared for a World Meteorological Organization report, which combined tree-ring and thermometer data, was misleading because it did not make clear how the data had been combined.
Inquiries by Pennsylvania State University into Michael Mann's conduct (2010), the US Environmental Protection Agency (2010) and the Inspector General of the US National Science Foundation (2011), which found no evidence of research misconduct or data manipulation.

Independent analyses of global temperature, including work by the Berkeley Earth project, founded by a physicist who had been skeptical of existing records, confirmed the warming trend found by the CRU and other groups.

The person or group responsible for the hack was never identified. Norfolk police closed their investigation in 2012, describing it as a sophisticated and carefully orchestrated attack.

What the evidence shows

The emails did not show that climate scientists fabricated or manipulated data to invent global warming. Their most quoted phrases referred to technical issues already discussed in the scientific literature. The investigations did identify real failings, including resistance to sharing data and to freedom-of-information requests, and a graph whose presentation was not transparent. Those are legitimate criticisms of conduct and openness, but they do not affect the conclusion, supported by multiple independent datasets and lines of evidence, that the Earth is warming because of human activity.

Lessons for readers

Short quotations from private messages can be made to say almost anything. Read them in context.
Scientific jargon often differs from everyday language. "Trick" can mean a clever method.
Distinguish between criticism of how scientists behaved and evidence that their findings are wrong.
Ask whether independent researchers, using different data, reach the same conclusion.

Sources

House of Commons Science and Technology Committee, The disclosure of climate data from the Climatic Research Unit at the University of East Anglia (2010).
Sir Muir Russell et al., The Independent Climate Change E-mails Review (2010).
Lord Oxburgh et al., Report of the International Panel set up by the University of East Anglia to examine the research of the Climatic Research Unit (2010).
National Science Foundation, Office of Inspector General, closeout memorandum (2011).
Berkeley Earth, global temperature analyses (2012 onward).