It is hot outside. This might not be notable except that it is late September and still in the mid-90s Fahrenheit, some 10 degrees warmer than usual for Atlanta according to the Weather Channel.
It is another hot day in a hot year. And it comes on the heels of the 2000s, which NASA’s Goddard Institute for Space Studies declared the hottest decade on record. It is, to many, one more piece of proof that the world is heating with unnatural rapidity as human industries churn out greenhouse gases.
Judith Curry doesn’t seem to notice the heat. As the afternoon sun beats down, she stands in a patch of grass on the Georgia Tech campus and poses for a photographer. Beads of sweat form on the photographer’s brow while maneuvering around Curry, snapping one photo after another. She is stoic, unbothered. Truth is, in the past year, Curry has grown accustomed to the heat.
In addition to serving as chair of Tech’s School of Earth and Atmospheric Sciences, Curry has become a renowned climate scientist. And when the debate over global warming erupted into all-out war with last year’s theft of private e-mails from climate scientists — known as Climategate — Curry had the temerity to break ranks and join those criticizing the scientists.
Staking out a position smack dab in the middle of those who warn of global warming’s existential threat to humanity and those who call it a hoax — alarmists and deniers, as they call each other — Curry has made herself a target of both camps. One science blogger labeled her climate change’s “inconvenient provocateur.” Climate modeler and blogger William Connolley suggested she’d suffered “a failure to think.”
Many of those who’ve criticized Curry have demanded she offer facts to support her assertions. They want to know what she thinks, what she believes about the climate.
The irony is that Curry isn’t caught up on what is known, what the research really shows. What drives her is all that remains uncertain.
Curry grew up in a suburb of Chicago. She says neither of her parents had any scientific inclination.
Her first push into science came in the fifth grade when a geologist spoke to her class. While a sophomore at Northern Illinois University, Curry was mulling a future in earth science when she took an introduction to meteorology class with a professor named Clayton Reitan.
“I ended up going the meteorology/climatology route,” Curry says. “It had a good teacher and a nice combination of physics, chemistry and earth science.”
At that point in the early 1970s, climate change “wasn’t on the table,” she says. Curry’s interest was the Arctic. Her PhD thesis at the University of Chicago was on the impact of sea ice and clouds on the radiation balance of the Arctic. She continued that research for a decade while serving as a faculty member at the University of Wisconsin, Purdue and eventually Penn State.
“That set me up very much to be involved in the climate change problem when, in the ’80s, that became more on the front burner,” Curry says.
Global warming became front-page news in 1988 when James Hansen, head of the Goddard Institute, delivered testimony to congressional committees that carbon dioxide in the atmosphere would cause increased temperatures, and that the impact would happen soon.
That same year, the World Meteorological Organization and the United Nations Environment Program, both under the umbrella of the United Nations, established the Intergovernmental Panel on Climate Change. The IPCC’s mission was to evaluate the risk of human-caused climate change and recommend policies to lessen its impact.
“The IPCC, they were the visible people,” she says. “As a rank-and-file scientist, I didn’t pay close attention and didn’t feel any particular reason to take a stand one way or the other. I was rather skeptical of some of the things Jim Hansen was saying. I didn’t think they were justified by the data we had.”
A select group of climate scientists from different countries formed the IPCC’s leadership, collaborating on climate change assessment reports. The first was released in 1990 and served as the foundation of the United Nations Framework Convention on Climate Change, a 1992 nonbinding international treaty to reduce greenhouse gas emissions.
Looking back, Curry sees the establishment of the IPCC as a harbinger of the trouble to come. Because the IPCC was tied to the United Nations treaty framework, the policy discussion influenced the scientists, she says. And environmental advocacy groups heavily supported the global warming movement, which further shaded the view of climate change.
As one of the IPCC’s lead authors, Keith Shine was quoted at the time in a Reuters article, “We produce a draft, and then the policymakers go through it line by line and change the way it is presented. … It’s peculiar that they have the final say in what goes into a scientist’s report.”
Climate change had become not a scientific question but a tool to push for environmental reform.
“The IPCC changed the way the entire topic has been framed,” Curry says. “With those kinds of roots, this is what you get.”
The debate over climate change was just heating up.
In 1995, the IPCC released a second assessment report, which forecast catastrophic global warming. Two years later, the United Nations Framework Convention on Climate Change was updated with the better-known Kyoto Protocol. As part of the treaty, 37 industrialized countries and the European Union committed to cutting production of greenhouse gases.
While the scientific community appeared committed to the belief in global warming, an opposition movement was beginning to form. Industries opposed the limiting of greenhouse gas emissions, claiming it would cause economic damage. Some politicians and economists warned that Third World countries could suffer because the protocol would limit their ability to generate energy.
Those who doubted global warming and opposed the protocol began to receive funding from utility companies and particularly the oil industry. A 2010 Greenpeace report found that Koch Industries, which owns refineries and operates pipelines, donated nearly $48 million to climate change opposition groups from 1997 to 2008.
The skeptics seized on comments like those of S. Fred Singer, an emeritus professor of environmental science at the University of Virginia, who in 1995 wrote a letter to IPCC contributing scientists to complain of changes made to the second assessment report by policymakers.
Singer noted that some phrases expressing doubt about global warming were deleted. One excised sentence stated, “Any claims of positive detection of significant climate change are likely to remain controversial until uncertainties in the total natural variability of the climate system are reduced.”
Singer concluded, “I believe we have here a clear example of the misuse of science — and of scientists.”
Then came the direst climate warning yet. In 1999, Michael Mann, a professor at Penn State University, released a paper that examined temperatures from the past thousand years. The temperatures remained flat until about 1900, when they spiked up suddenly and continued escalating. The chart’s shape earned it the nickname the hockey stick graph.
The graph was featured prominently in the IPCC’s third assessment report in 2001, and Mann became one of the leading figures of climate science. His research became a subject of inquiry for those who doubted global warming. One of the most well known of these, Stephen McIntyre, began requesting Mann release the data that went into the report.
The 2001 report also received criticism from one of its lead authors. Richard Lindzen, an MIT meteorology professor, wrote that IPCC officials and policymakers significantly changed a draft prepared by scientists to play up the threat of global warming.
“There may not have been any significant warming in the last 60 years,” Lindzen wrote. “Moreover, such warming as may have occurred was associated with jumps that are inconsistent with greenhouse warming.”
In 2002, Curry was appointed to her current position at Georgia Tech. Through her research and appointments to prestigious committees and boards of the World Meteorological Organization, the National Research Council, NASA and the National Oceanic and Atmospheric Administration, she was becoming increasingly known in the climate change community.
She was tapped in 2003 to suggest ideas for a workshop on uncertainty in climate science, and she suggested a focus on characterizing and understanding uncertainty in data and climate models. But the workshop ended up focusing on communicating uncertainty to policymakers rather than trying to understand it.
“I wasn’t criticized in 2003, I was ignored,” Curry says. “It was an idea that was floated, and nobody wanted to hear it at the time. They were on a different wavelength.”
At that point, Curry’s research had shifted from the Arctic to tropical storms. Particularly, she had found that tropical storms and hurricanes were increasing in intensity and that global warming would only exacerbate the storms. The findings were published in the journal Science in 2005, three weeks after Hurricane Katrina devastated New Orleans.
The timing was “uncanny,” Curry says. It instantly brought her media attention and, for the first time, a prominent place among climate scientists engaged in the public debate on climate change.
“Maybe for a few years I was adopted into that clique circa 2005 after the hurricane paper,” Curry says. “I made public statements supporting the IPCC findings. I had my questions, but I felt like that was the responsible thing to do.”
Curry wasn’t alone in supporting the IPCC. In 2007, the panel released its fourth assessment report, which stated “warming of the climate system is unequivocal” and had the support of thousands of scientists from dozens of countries.
The IPCC shared that year’s Nobel Peace Prize with Al Gore, who was the primary subject of the 2006 global warming documentary An Inconvenient Truth.
Public opinion polls showed that belief in global warming as a threat was higher than it had ever been. But the nonbelievers were far from giving up.
On Nov. 17, 2009, the servers of several climate science blogs were hacked, and the hackers attempted to post more than 1,000 e-mails and 3,000 other documents.
It was quickly discovered that the e-mails and documents had been stolen from a server used by the Climatic Research Unit at East Anglia University, the British holder of global temperature records. The e-mails were private correspondence between several of the top climate scientists, most of them closely involved with the IPCC. Soon, claims were made that the e-mails poked holes in the certainty of global warming.
The hacker had copied the data to several locations around the Internet, including some Web sites of global warming skeptics, by Nov. 19. The hack soon began receiving mention online and in the mainstream media. In the following days and weeks, several of the involved scientists received death threats. The disclosure of the e-mails became known as Climategate.
Shortly after the e-mails were leaked, Curry saw some online and knew they were real.
“Many of my peers thought it was just an illegal hack that we could ignore,” she says. “I saw it as a threat to the IPCC and all of climate science, largely because of this trust issue.”
The trust issue, Curry says, is that scientists are expected to maintain the highest ethical standards and not let outside influences shape their findings.
According to Fact Check and other independent organizations, the e-mails don’t invalidate global warming research. Many skeptics seized on the phrase “hide the decline” in one e-mail, but given proper context, the quote didn’t reflect a willful mischaracterization of data.
The e-mails do shed light on a group of scientists who were perhaps overly certain of themselves and overly caustic toward critics. Global warming criticism was referred to as “fraud” and “pure crap” in some messages.
Curry says the scientists had “some hubris in having too much confidence in what they were doing” and were too engaged with the politics of the debate. Scientists also made efforts to block Freedom of Information Act requests from McIntyre and other skeptics, the e-mails show.
“I had trusted those guys,” Curry says. “But when I saw all this about what really goes on behind closed doors, how these conclusions are reached, how they try to put down skeptics, I felt like the IPCC had lost the moral high ground. I didn’t feel the same obligation to support their findings, particularly their conclusions based on expert judgment.”
Curry decided to publicly voice her viewpoint on the e-mails. While many scientists were taking a “circle the wagons” approach, she says she recognized that climate scientists needed to work quickly to regain the public trust.
Her first writing on the subject was published Nov. 22, 2009, on McIntyre’s Web site climateaudit.org. She warned of significant damage to public credibility caused by a lack of transparency, “tribalism” among some in the climate research community and unwillingness to engage with skeptics.
A week later, Curry wrote a second missive, an open letter to graduate students and young scientists to reaffirm basic research values.
She wrote, “A better understanding of the enormous policy implications of our field should imbue in all of us a greater responsibility for upholding the highest standards of research ethics.”
“What bothered me the most was how climate researchers looked to the public, especially to educated and technical people,” Curry says of posting the messages. “They expect higher standards.”
Curry expected that other scientists would come forward with similar responses, but she was nearly alone.
Needless to say, Curry lost her place in the IPCC clique. At the 2010 Google Science Foo Camp in August, Curry and Mann, whose work she has criticized, were both in attendance. The two avoided each other, Curry says.
Climateprogress.org, which has been called the most influential climate blog by Time magazine, responded critically to Curry’s essays. Her opinions were called “unconstructive,” full of “factual misstatements” and “completely at odds” with her previous position on global warming.
Her stance didn’t completely defrost her relationship with global warming skeptics either. Blogger and skeptic Anthony Watts only grudgingly published one of Curry’s essays, with the caveat that he opposed her use of the term “deniers” to describe skeptics.
Meanwhile, investigations into Climategate explored both the crime of the hack and whether the e-mails revealed any scientific wrongdoing. The criminal inquiries have yet to turn up the hacker, and the various other investigations — conducted by institutions such as the British House of Commons and Penn State University — vindicated the scientists aside from some “misleading” conclusions.
That did little to temper the criticism of the IPCC, Mann and other top climate scientists. Clive Crook, a senior editor at The Atlantic, wrote of the inquiries, “At best they are mealy mouthed apologies; at worst they are patently incompetent and even willfully wrong.” John Tierney of The New York Times added, “When a journal publishes a skeptic’s paper, the scientists e-mail one another to ignore it. They focus instead on retaliation against the journal and the editor.”
As Curry predicted, Climategate also led to a heightened distrust of climate scientists from the American public. A December 2009 Rasmussen Reports poll showed that 52 percent of Americans believed there existed significant disagreement among scientists about global warming. And 59 percent believed it was somewhat likely scientists had falsified data, while 35 percent believed it was very likely.
For her part, Curry doesn’t believe any scientists acted maliciously.
“I don’t think anybody’s come at this with bad motives,” she says. “It’s really about believing their models and thinking we should do something about it based on what the models say. … And even if you could have 100 percent confidence in the models, that doesn’t necessarily prescribe what you should do in terms of policy.”
During the fallout of Climategate, policymakers and politicians from around the world slowed or stopped pushes for climate legislation, Curry says. “There are all sorts of reasons to work toward clean energy, but as far as climate change being a driver of that, I think it’s lost an enormous amount of traction.”
Instead of simply trying to curb greenhouse gas emissions on a global scale, Curry advocates making humanity less vulnerable to extreme events such as hurricanes and focusing on regional issues. In Atlanta, for example, global warming is less of a concern than water. Droughts and floods create significant problems for the rapidly growing population.
While scientists shouldn’t be afraid to engage with the public or policymakers, Curry says the climate debate reveals the downside of scientists becoming too involved in politics.
“The sad thing is what should’ve been a political debate was fought over details of the science,” she says. “Part of this is the fault of the scientists. Scientists recommended policy for greenhouse gas stabilization. … The scientists became the pawns in the political debate over energy policy.”
Curry doesn’t blame individual scientists but rather institutions such as the IPCC. Her view was echoed in an August 2010 report by the InterAcademy Council that stated the IPCC “needs to fundamentally reform its management structure and strengthen its procedures.”
Curry says the panel “needs to change the way they do business or they risk becoming irrelevant. The IPCC relies more on experts than science. They put forth a lot of circumstantial evidence, but they don’t put it forward in an argument with the uncertainty, which is needed to make their arguments more airtight.”
Despite those in the climate change camp who question Curry’s allegiance, she’s concerned about her own impact on the environment. She drives a Toyota Prius hybrid and walks from her midtown Atlanta home to her office on the Tech campus.
Her office isn’t overly decorated, though two large paintings hang from the walls. One shows an island, gray and dead, with two volcanoes rising into the dark sky. It has a vaguely apocalyptic feel. The other is dominated by an orange-red globe that seems to be on a stage.
The paintings were done by Curry’s daughter, Meredith. Curry says she chose them for the abstract way they evoke Earth and surrounding planets.
Another wall displays framed editorial cartoons. One features Curry popping out of a trash can labeled “Climate Science.” She’s holding a piece of paper and saying, “I found a good bit.” Another cartoon features Curry as Joan of Arc. She wears chain mail armor and is labeled the patron saint of climate science as she literally throws down her gauntlet.
In the past year, that often has been the perception of Curry: a scientist out picking fights, an inconvenient provocateur. But that hasn’t been her mission at all, she says. Instead, she is trying to bring together the polarized sides of climate debate and return scientists’ focus to thorough research.
“The criticism [of the essays] was from the mainstream climate blogosphere,” Curry says. “In terms of scientists who stay out of the public debate, I feel like I got a lot of support.
“Scientists involved in the public debate mainly were trying to protect the UN treaty and were worried my post was going to make things worse. But that’s about policy and not about science. If that’s what was making these people tick, they’re part of the problem. That’s how we got in this trouble in the first place.”
Curry also says she felt supported in her efforts by colleagues and the administration at Tech, as well as the Institute’s alumni, who have sent Curry supportive e-mails and commented positively on her posts on climate blogs.
Asked if she felt any regrets about her responses to Climategate, Curry says she only wished she had started her own blog initially instead of submitting posts to different sites and getting into debates with commenters.
“I’ve gotten caught up in lots of little blogospheric tempests,” she says of her online forays. “I think the blogosphere can be potentially very important, but most scientists don’t like to do it because it can be blood sport.”
In September, she started her own blog, Climate Etc., hosted at judithcurry.com. From the beginning, her posts were receiving hundreds of views and comments.
Her public engagement has driven Curry’s research interests into the sociology and philosophy of science. She’s begun looking into the process of group learning and the wisdom of crowds as well as the potential pitfalls of highly charged research areas like climate change, in which statements can become political fodder or affect funding.
Beyond her administrative, research and blogging duties, Curry also is the president of the Climate Forecast Applications Network, a clean technology company she founded with Peter Webster, a professor of earth and atmospheric sciences at Georgia Tech.
That leaves little free time, though she says she tries to fit in her only hobbies: hiking with her dogs, yoga and reading. And she makes time for posing for photos, as on a particularly hot September day.
She’s asked about these bits of news, that the temperature has been hovering well above historic averages, that NASA is calling the 2000s the hottest decade on record. After Climategate, what do pronouncements such as those mean?
“An individual record doesn’t say anything about climate change,” Curry says. “The historical records are pretty short, and we don’t have a lot of data over the oceans prior to 1960. There’s not a lot of context for some of these statements. You can’t read too much into them.”
One of the great frustrations over climate change is that it seems there would be consensus. Is the climate warming or not? Are humans causing it? Don’t the scientists have a conclusive answer?
The climate is an extremely chaotic system, one affected by solar variations, volcanic activity, ocean oscillations and other factors, Curry says. The major problem with the IPCC reports and some research that was exposed during Climategate was unwarranted confidence, she says.
The climate’s natural variability is unpredictable. Greenhouse gas emissions could offset a natural cooling trend or amplify a heating trend. “It could even mean the plausible worst-case scenario is worse than anything we’ve imagined,” Curry says.
“It’s a very complex scientific problem. There’s a lot of uncertainty,” she says. “It’s not that we’re incompetent, there’s just a lot of inherent variability. A lot of that is unknowable.”
The question then naturally arises. What is Judith Curry sure about?
She pauses before giving an answer in three parts.
“Climate always changes,” she says.
“Carbon dioxide, all other things being equal, will contribute to a warmer planet.”
And lastly, “Whether in the coming century greenhouse gas will dominate natural variability remains to be seen.”
Asked what she is certain of, her most definitive answer is uncertainty itself.