A little more than a year ago, there was a feeling among many editors and reporters that the climate-change story had, in a sense, progressed since the release of the Intergovernmental Panel on Climate Change’s (IPCC) watershed Fourth Assessment Report in 2007.
Following the release of that report, coverage of climate science soared, with innumerable articles laying out the basics of the greenhouse effect, the carbon cycle, and how scientists know the Earth is warming at an unusual pace and why human industry is most likely responsible. Appropriately, articles quickly moved on to stories about the politics and economics associated with addressing the problem. To a large extent, the climate story became the energy story.
Then came the unauthorized release of a large cache of controversial e-mails from prominent scientists in the United Kingdom and United States, the failure of the Copenhagen climate summit, the revelation of minor errors in the IPCC’s 2007 report, and the failure of climate legislation in Congress. As my colleague Cristine Russell recently pointed out, “It’s been a challenging time for the climate change story on just about every front.”
The adversity is causing some journalists to revisit the basics of climate science in a very satisfying way, however. Two articles on Wednesday offered great refreshers on why scientists know two very important things: that atmospheric carbon dioxide is rising and that global temperature is rising. As the Knight Science Journalism Tracker observed, the long features “provide a serious, handy, collective guide to the yin and yang of observational climatology’s primary jobs these days - explaining and measuring global warming.”
The New York Times’s Justin Gillis was responsible for the piece about measuring the steady increase in atmospheric carbon dioxide. In essence, it is a profile of the scientist Charles D. Keeling, who died in 2005, how he learned to measure the concentration of CO2 in the air, and how he charted its rise along with the help of his son, Ralph, who carries on his work. As the Tracker’s Charlie Petit pointed out, it’s a story that “has been told many times,” but the front-page treatment, followed by a double-truck after the jump, was a high-profile way to reintroduce readers to the famous (among scientists, at least) Keeling Curve. Moreover, Gillis also weaves in the parallel story of the so far fruitless efforts to restrict global greenhouse-gas emissions, bringing readers right up to the recent United Nations summit in Cancún.
The smart decision to ground the explanatory science in current events was also on display in the article about why scientists know worldwide temperatures are rising, which was written for Climate Central by Tom Yulsman, co-director of the University of Colorado’s Center for Environmental Journalism. The piece starts with a newsy discrepancy: NASA’s Goddard Institute for Space Studies (GISS) recently announced that November was the warmest November on record, while the National Climatic Data Center said it was the second warmest November. From there it provides an excellent explanation of three primary groups that track surface temperatures, their methods, how they handle gaps and biases in their data, and, most importantly, why the groups’ datasets are in close agreement, despite the fact they’re not identical.
Side-by-side, Gillis and Yulsman’s articles explain the two most fundamental phenomena underlying global warming - rising carbon dioxide and rising temperatures. Neither piece really discusses the bridge in the relationship - temperature’s “sensitivity” to increasing carbon dioxide. Thankfully, Gillis got to write this follow-up post on the Times’s Green blog.
Pennsylvania State University climatologist Richard B. Alley, whom Gillis quoted in his article, seems to have the prompted the post. In his article, Gillis presented “one of the canonical projections of climate science”—that the average surface temperature of the earth is likely to increase by five or six degrees Fahrenheit, with a doubling of carbon dioxide in the atmosphere—and contrasted that with a prediction from skeptics, who say that the increase is likely to be less than two degrees. Apparently, Alley got in touch with Gillis to say:
[He] gets annoyed by the way this contrast is often presented in news accounts. The higher estimate is often put forward as a worst case, he pointed out, while the skeptic number is presented as the best case.
In fact, as Dr. Alley reminds anyone who will listen, and as he recently told a Congressional committee, the estimate of 5 or 6 degrees is actually mildly optimistic. Computer programs used to forecast future climate show it as the most likely outcome from a doubling of carbon dioxide, but those programs also show substantial probabilities that the warming will be much greater.