The manufactured controversy over emails stolen from the University of East Anglia's Climatic Research Unit has generated a lot more heat than light. The email content being quoted does not indicate that climate data and research have been compromised. Most importantly, nothing in the content of these stolen emails has any impact on our overall understanding that human activities are driving dangerous levels of global warming. Media reports and contrarian claims that they do are inaccurate.

Investigations Clear Scientists of Wrongdoing

Six official investigations have cleared scientists of accusations of wrongdoing.

Other agencies and media outlets have investigated the substance of the emails.

The Environmental Protection Agency, in response to petitions against action to curb heat-trapping emissions, dismissed attacks on the science rooted in the stolen emails.

Factcheck.org debunked claims that the emails put the conclusions of climate science into question.

Politifact.com rated claims that the emails falsify climate science as "false."

An Associated Press review of the emails found that they "don't undercut the vast body of evidence showing the world is warming because of man-made greenhouse gas emissions."

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Some news organizations have misreported critical aspects of the stolen email story. There is no evidence scientists did anything with temperature data they weren't already doing openly in peer-reviewed papers.

At this time, there is no evidence that scientists "fudged," "manipulated" or "manufactured" data. These unsupported claims, based on taking the emails out of context, are being promoted by long-time anti-science opponents of climate change legislation. The U.N. Intergovernmental Panel on Climate Change (IPCC), the University of East Anglia and Penn State University are separately looking into the contents of the stolen emails to assess these claims.

While the emails have raised some concerns, the email content being quoted does not indicate that climate data and research have been compromised. Most importantly, nothing in the content of these stolen emails has any impact on our overall understanding that human activities are driving dangerous levels of global warming. Media reports and contrarian claims that they do are inaccurate.

University of East Anglia Climatic Research Unit Director Phil Jones wasn't "hiding" anything that wasn't already being openly discussed in scientific papers. He was using a "trick"—a technique—published in the peer-reviewed scientific literature.

This email exchange from 1999 seems to refer to scientists examining past climate data and communicating with one another about it. In particular, Jones is talking about how scientists compare temperature data from thermometers with temperature data derived from tree rings. Comparing that data allows scientists to derive past temperature data for several centuries before accurate thermometer measurements were available. The global average surface temperature since 1880 is based on thermometer and satellite temperature measurements.

The "trick" is actually a technique (in other words, a "trick of the trade") used in a peer-reviewed, academic science journal article published in 1998. "Hiding the decline," another phrase that has received much attention, refers to another technique used in another academic science journal article. In any case, no one was tricking anyone or hiding anything. Rather, this email exchange shows scientists communicating about different ways to look at the same data that were being discussed at the time in the peer-reviewed literature. Later the same data were discussed at length in a 2007 IPCC report.

In some parts of the world, tree rings are a good substitute for temperature record. Trees form a ring of new growth every growing season. Generally, warmer temperatures produce thicker tree rings, while colder temperatures produce thinner ones. Other factors, such as precipitation, soil properties, and the tree's age also can affect tree ring growth.

The "trick," which was used in a paper published in 1998 in the science journal Nature, is to combine the older tree ring data with thermometer data. Combining the two data sets can be difficult, and scientists are always interested in new ways to make temperature records more accurate.

Tree rings are a largely consistent source of data for the past 2,000 years. But since the 1960s, scientists have noticed there are a handful of tree species in certain areas that appear to indicate temperatures that are warmer or colder than we actually know they are from direct thermometer measurement at weather stations.

"Hiding the decline" in this email refers to omitting data from some Siberian trees after 1960. This omission was openly discussed in the latest climate science update in 2007 from the IPCC, so it is not "hidden" at all.

Why Siberian trees? In the Yamal region of Siberia, there is a small set of trees with rings that are thinner than expected after 1960 when compared with actual thermometer measurements there. Scientists are still trying to figure out why these trees are outliers. Some analyses have left out the data from these trees after 1960 and have used thermometer temperatures instead.

Techniques like this help scientists reconstruct past climate temperature records based on the best available data.

In another email, Kevin Trenberth, a climate scientist at the National Center for Atmospheric Research in Colorado, wrote that systems for observing short-term annual climate variation are inadequate and complained: "The fact is that we can't account for the lack of warming at the moment, and it is a travesty that we can't…. Our observing system is inadequate."

Scientists have high confidence about global temperature trends over recent decades because those observations are based on a massive amount of data. That's why we can say with certainty that over the past several decades, the Earth has warmed. We can also say with certainty that continuing to overload the atmosphere with carbon dioxide will cause it to warm further.

But scientists are still trying to understand how the climate shifts in the short term, on a year-to-year basis for instance. In this email, Trenberth is bemoaning the lack of monitoring equipment in the ocean and atmosphere around the world that would give scientists more information to help understand exactly how short-term climate variation happens. In particular, he references 2008, which was cooler than scientists expected, but still among the 10 warmest years since instrumental records began.

The sentiments in Trenberth's private email reflect his public communication. Trenberth talked about this same issue in a scientific paper in 2009 (pdf), in which he addresses this exact question.

There is no clear evidence to date that scientists violated important principles of scientific integrity. And the emails do not undermine the science.

Some emails relating to avoiding freedom of information requests and keeping articles out of journals have raised concerns about scientific integrity. Scientists should always be as open as possible with their data and methods. Transparency is critical for accountability on all sides. For his part, Phil Jones claims he didn't delete any email messages in response to freedom of information requests. If he did, that conduct would be wrong. But to date, there is no evidence that any emails were deleted.

Science must be viewed in context. When one places the emails in context, they don't amount to much—and as noted above, they do not undermine climate data or research. Likewise, it is important to understand the scientific integrity claims against the scientists in context.

Regardless of whether the University of East Anglia's Climatic Research Unit staff complied with freedom of information requests, their data is still rigorous and matches the three other independent temperature data sets at NASA, the National Oceanic and Atmospheric Administration and the Japanese Meteorological Society.

Much has been made about emails regarding a certain paper that some scientists did not think should have been published in a peer-reviewed academic journal. These emails focus on a paper on solar variability in the climate over time. It was published in a peer-reviewed journal called Climate Research, but under unusual circumstances. Half of the editorial board of Climate Research resigned in protest against what they felt was a failure of the peer review process. The paper, which argued that current warming was unexceptional, was disputed by scientists whose work was cited in the paper. Many subsequent publications set the record straight, which demonstrates how the peer review process over time tends to correct such lapses. Scientists later discovered that the paper was funded by the American Petroleum Institute.

In a later e-mail, Phil Jones references two other papers he didn't hold in high esteem. "I can't see either of these papers being in the next IPCC report. Kevin and I will keep them out somehow - even if we have to redefine what the peer-review literature is!"

Yet, the papers in question made it into the IPCC report, indicating that no restrictions on their incorporation were made. The IPCC process contains hundreds of authors and reviewers, with an exacting and transparent review process.

The fact that groups opposing action on climate change are crying "conspiracy" shows how desperate they are to discredit scientists.

The thousands of stolen emails span more than a decade. Whoever stole them could only produce a handful of messages that, when taken out of context, might seem suspicious to people who are not familiar with the intimate details of climate science.

Opponents of climate action have been attacking climate science for years. The fact that out-of-context personal attacks on scientists are the most successful argument they can offer speaks volumes about their failure to gain any traction by arguing against the evidence.

Their strategy has unfortunate consequences, too. On December 8, the Guardian reported that University of East Anglia scientists have been receiving death threats.

The timing of the publication of these emails should make us suspicious about the motivations of the people who hacked them.

The stolen emails were published just two weeks ahead of a major U.N. climate change conference in Copenhagen. According to a British newspaper, they were originally hacked in October. Whoever published these emails likely wanted to spread misinformation about climate science to try to undermine the conference. The University of East Anglia, which housed the emails, has launched an investigation to determine who stole them.

Scientists are as human as anybody else.

Some of the other emails simply show scientists expressing frustration and—in one email—even talking (not seriously, we hope) about beating up someone who had, in his view, made an unfair, public attack on his colleague. Such chatter is not surprising to find in private emails. But they have generated widespread attention in part because they don't mesh with the public's image of scientists.

Scientists have a wide array of dispositions. But regardless of how scientists act, they should all advance their arguments through evidence and valid scientific interpretations. The process of science is what is important. Over time, rigorous analyses, vetted through expert peer review, tend to weed out poorly substantiated arguments. And only the best explanations for how the world works—such as the obvious evidence that excess carbon dioxide emissions are driving global warming—survive the process.