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Naomi Oreskes—Scientific Consensus, Climate Change, and the Merchants of Doubt

Photo Credit Vincent Verdi 

It was just a little thing—a single slide in an otherwise busy presentation—but it would alter the course of her career, change forever how climate change was reported in the media, and ultimately lead to attacks and counterattacks.

As a historian of science with a philosopher’s disposition and a love of literature, Harvard professor and AAAS Fellow Naomi Oreskes’ professional preoccupation has been with how science knows what it knows, how scientific theories change and are overthrown, and how scientists ultimately arrive at an informed consensus that defines their fields’ collective knowledge.

Born in 1958, Oreskes said she fell into science because, growing up during the Cold War with the specter of the Soviet Union’s sputnik whirling above her, it was expected. 

Yet for someone with such diverse interests, Oreskes initially chose a grounded field: geology. She spent the early 1980s working in the Australian Outback for the Western Mining Corporation, then the country’s third largest mining interest. However, the work didn’t captivate her for long and soon she was back in school.

Oreskes’ intent as a graduate student was to investigate an ore deposit. Her professors pushed her to ask the bigger questions, which pushed Oreskes, something of a contrarian at heart, to ask why her practical interests weren’t being taken seriously. So she decided to branch out.      

Oreskes took a course in the philosophy of science in the hope of becoming a better scientist. It was an auspicious choice, for although the class was on the philosophy of science it was being taught by a historian of science. Oreskes had finally found a field that could accommodate her diverse interests. 

“As a historian, being able to write, being interested in literature, being interested in the political and social dimensions of science, this isn’t a liability this is a strength. That was my eureka moment, when I knew that this is where I belong,” Oreskes said.

Oreskes has attempted to understand how some very heady concepts have played out historically.

“The questions I’m interested in are philosophical, intellectual, epistemological, and also political. I came to the conclusion that the best way to try to answer these questions was through historical investigations,” Oreskes said.

Oreskes’ philosophical interest boils down to a deceptively simple question: How can we trust science?

Of course, many people do not trust science—be it climate science or the science supporting the efficacy of vaccines. The reason for that, Oreskes said, is because most people lack the training to verify scientific claims. It's not just a problem for nonscientists. Scientists also have difficulty verifying claims outside their fields of expertise. So why should we trust science? Oreskes said the answer doesn’t so much have to do with method as with consensus.

From believing that Earth was the center of the universe to the belief that the continents do not move, the history of science is rife with examples of false theories holding on for too long.

What leads to this overthrow? Oreskes said it’s not so much about the rogue geniuses, the Newtons and Einsteins, shaking things up, but about the lively, informed, and often powerfully argumentative and skeptical discussions and debates that happen among scientists. When this heated social activity leads to consensus, Oreskes said it should be taken seriously.

So when Oreskes was asked to give a talk for AAAS in 2004 on just that, she initially decided to focus on what had been her forte: the history of the theory of plate tectonics, a subject that as a geologist she has returned to several times, including in her book The Rejection of Continental Drift.

To make the discussion more contemporary, Oreskes added one slide about a scientific consensus that had been arrived at more recently: Climate change is happening and it is caused by human activity. To her surprise, this was what resonated with her audience.

“People came up to me afterwards, saying ‘Where did you publish this?’” she said.

In fact, Oreskes hadn’t published these findings, largely because she didn’t think they were newsworthy. She'd intended to make a philosophical point but ended up making a political splash. The slide contained a review of the climate science literature, showing that a belief in human-made (anthropogenic) climate change was now the informed opinion of the majority of climate scientists. It was a notable first.

At the urging of colleagues, she submitted her research to AAAS’s Science, turning that slide into a one-page write-up. It was widely cited. Then came the attacks.

“I didn’t see that paper as particularly controversial, but then I started getting hate mail,” said Oreskes.

She wasn't the first to catch heat. While working on an official history of atmospheric science at NASA, historian Erik Conway came across a series of documents that pointed to what appeared to be a concerted effort to discredit scientists who connected the depletion of stratospheric ozone to human-made compounds, such as refrigerants and aerosols.

The political attacks were not the subject of his official history so Conway left them out. But he kept his notes and passed them along to Oreskes.

In the files, Oreskes read about a series of attempts to discredit Sherwood Rowland, the Nobel laureate and one-time president of AAAS who was also the first researcher to tie the destruction of the ozone layer to Chlorofluorocarbons, or CFCs, including human-made freons in spray cans and refrigerators. The attacks on Rowland looked familiar to Oreskes.

“It was like you could take out ‘Rowland’ and put in ‘Oreskes,’ take out ‘ozone’ and put in ‘climate change,’” she said.

Oreskes kept digging and discovered that the people who had worked to discredit Rowland were some of the same people who had tried to discredit her and that these same people had also worked to help discredit scientists linking tobacco to cancer. 

“At that point I called Erik [Conway] up and said, ‘I think we have a story here,’” said Oreskes.

That story evolved into a book, Merchants of Doubt. Published in 2010 and since made into a documentary, Oreskes and Conway’s book outlines various attempts to discredit scientific research by fueling controversies where there are none. Oreskes and Conway documented attempts to discredit scientists linking cigarette smoking to cancer, CFCs to ozone depletion, and climate change to the burning of fossil fuels. 

Read something about climate change these days and you’re likely to see something about the overwhelming scientific consensus. So-called balanced stories that present the view of both climate change believers representing the majority scientific consensus and deniers representing the minority are now the exception. This is Oreskes’ victory.  

Now, she has become something of a climate science crusader, raising money to aid researchers who have been attacked, while also pushing universities to divest from the fossil fuel industry. She was front and center at the recent protest of climate researchers at December's American Geophysical Union (AGU) conference and she plans to attend the  March for Science, which was endorsed by both AGU and AAAS.     

“To me, it’s clear that we [scientists] need to stand up and be counted and we need to defend the integrity of scientific research and the integrity of scientific findings because if we don’t do it, nobody is going to do it for us,” Oreskes said, continuing, “Facts don’t speak for themselves, people need to speak for facts.”

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