As scientists' level of confidence that human activities are contributing to significant changes in the Earth's climate increases, the amount of "hedging" language used by some prominent journalists in writing on that subject has also risen, a team of University of Colorado researchers has found.
"The language itself is very important for how people perceive the information," said Adriana Bailey, a doctoral student at the CU's Cooperative Institute for Research in Environmental Sciences and lead author on a newly published study.
"And so what we wanted to look at is what kind of language choices are being made to discuss the scientific uncertainties that do exist ... or to construct new uncertainties that might be extrinsic to the science."
Bailey and her colleagues studied articles in two U.S. papers, the New York Times and the Wall Street Journal, as well as two Spanish papers, El Mundo and El Pais. Articles used for the study were published in 2001 and 2007, years when the Intergovernmental Panel on Climate Change released its third and fourth assessments of the physical science basis for climate change.
The study, which was published Monday in the journal Environmental Communication, also found that the two newspapers in the U.S. use more hedging language in climate stories than their Spanish counterparts.
Surprise that 'hedging' has climbed
The researchers examined the articles for words that typically suggest uncertainty, such as "almost" and "speculative." Then they considered the context in which they appeared to decide whether they should count as hedging language.
For example, the word "uncertainty" was counted in a New York Times article that read " ... substantial uncertainty still clouds projections of important impacts ... ." It was not counted in a sentence from the same newspaper that read " ... uncertainty was removed as to whether humans had anything to do with climate change. ..."
Also, the researchers only counted hedging language that had to do with either the physical science basis for climate change or the IPCC process.
They found that in 2001, the U.S. papers used 189 hedging words or expressions for every 10,000 words printed, while the Spanish papers used 107. In 2007, the number of hedging words and expressions used per 10,000 words was up to 267 in the U.S. and 136 in Spain.
"I think I did find it surprising that there was more hedging language used over time," said Maxwell Boykoff, a CIRES fellow and assistant professor in environmental studies at CU and co-author on the study.
"It kind of goes against the grain of that increasing certainty about the changing planet."
Boykoff cited as factors the "increasingly politicized atmosphere" surrounding climate change, as well as the economics of contemporary journalism, where reporters "in shrinking newsrooms face increasing pressure to meet deadlines, covering a wider range of issues," which he sees as "especially difficult when it comes to such a complex and nuanced story as climate change."
'The reporting has been somewhat disappointing'
The freshest data in the study dates to the IPCC report of 2007 and does not include reporting concerning the latest IPCC report, known as the fifth assessment, published in phases over the past nine months.
"Unfortunately, that's part of the slowness of academic publishing," Bailey said. "We actually completed the study a year ago," ahead of the most recent IPCC report. "We were hoping it would come out before. So it goes."
Bailey said she would be interested to see if the pattern detected in comparing the 2001 and 2007 IPCC reports held true for the IPCC's recently published fifth assessment.
Additionally, she said, there could be merit in "looking a little more closely at whether this level of hedging is isolated to climate change science, or whether you see this generally in all types of science stories.
"Is there simply a tendency to hedge a lot when we write about science? Or are we using more ambiguous language when we write about climate science, specifically?"
Kevin Trenberth, a distinguished scientist in the climate analysis section at the National Center for Atmospheric Research and contributor to the IPCC reports, has not read the study by Bailey and her colleagues. But he did not express surprise at their findings.
"The whole of the journalistic enterprise is changing substantially," Trenberth said. "The number of environmental reporters, the number of people who have expertise on these kinds of things, has clearly changed, and it relates very much to the troubles that written media have, versus the Internet.
"There are clearly some changes of that nature underway. I would say, generally, that the reporting has been somewhat disappointing."
The third co-author on the study was Lorine Giangola, STEM coordinator for the Graduate Teacher Program at CU.
Contact Camera Staff Writer Charlie Brennan at 303-473-1327 or firstname.lastname@example.org.