On the March 21 edition of National Public Radio's (NPR) Morning Edition, science correspondent Richard Harris reported that “scientists do quibble a little bit about some of the facts that” Vice President Al Gore has cited while discussing global warming both in his film An Inconvenient Truth (Paramount Classics, 2006) and elsewhere. As an example, Harris asserted that in December 2006 “Gore said that Arctic ice could be gone entirely in 34 years,” which, according to Harris, “no one can say” with such “certainty.” In fact, in his speech, Gore was apparently citing a research study released three days prior, which found “that the ”recent retreat of Arctic sea ice is likely to accelerate so rapidly that the Arctic Ocean could become nearly devoid of ice during summertime as early as 2040," or 34 years from when Gore made his remarks.

Further, in introducing the segment, host Renee Montagne stated that because Gore “is firmly in the spotlight on this issue, so are his detractors. They include some scientists who are concerned about global warming but have raised questions about Al Gore's data and some of his conclusions.” But neither Montagne nor Harris provided any examples of specific scientists who “have raised questions about” Gore's “data” and “conclusions.” As Media Matters for America noted, The New York Times asserted in a March 13 article that critics of the film and of Gore's work are not confined to those on the fringe. But the Times then proceeded to cite a parade of well-known global warming skeptics who have made statements questioning global warming that have either been debunked or discredited by the scientific community.

Arctic ice melt

Harris asserted that during a December 14, 2006, “talk at the American Geophysical Union meeting ... Gore said that Arctic ice could be gone entirely in 34 years, and he made it seem like a really precise prediction.” Harris added: "[T]here are scary predictions about what's going to happen to Arctic sea ice in the summertime, but no one can say '34 years.' That just implies a degree of certainty that's not there. And that made a few scientists a bit uncomfortable to hear him making it sound so precise."

But according to a San Francisco Chronicle article on Gore's presentation, Gore himself did not assert that the Arctic ice “could be gone entirely in 34 years.” Rather, he cited a recent scientific study estimating that by 2040 the Arctic ice will melt almost entirely during summertime. It is unclear whether Gore explicitly claimed that the “Arctic ice could be gone entirely,” as Harris asserted. From the December 15, 2006, article:

Even after 40 years of following the science of climate change, he said he was surprised to learn this week about new, earlier projections for when the Arctic sea ice will completely melt during the summertime. That research came from scientists at the National Snow and Ice Data Center at the University of Colorado.

“I was shocked that their horizon was 34 years under a business-as-usual scenario. If we allow it to go, it won't come back under any timetable relevant to the human species,'' Gore said.

While the Chronicle reported that Gore was citing research ”from scientists at the National Snow and Ice Data Center at the University of Colorado," Gore actually appeared to be referring to a joint research project, funded by the National Science Foundation and NASA and conducted by researchers from the National Center for Atmospheric Research (NCAR), the University of Washington, and McGill University. Contrary to Harris' claim that “no one can say” that the Arctic sea ice could be gone in “34 years,” these researchers found that the “recent retreat of Arctic sea ice is likely to accelerate so rapidly that the Arctic Ocean could become nearly devoid of ice during summertime as early as 2040”. As a December 11, 2006, NCAR article on the study noted, the researchers ran “scenarios ... on supercomputers,” which “show[ed] that the extent of sea ice each September could be reduced so abruptly that, within about 20 years, it may begin retreating four times faster than at any time in the observed record.” The article further noted that one “model simulation” found that "[b]y 2040, only a small amount of perennial sea ice remains along the north coasts of Greenland and Canada, while most of the Arctic basin is ice-free in September."

This projection appeared to be bolstered by a recently released study by researchers at the National Snow and Ice Data Center at the University of Colorado. According to a March 15 NASA "media alert," the researchers found that "[b]ecause temperatures across the Arctic have risen from 2 degrees to 7 degrees F. in recent decades due to a build-up of atmospheric greenhouse gases, there is no end in sight to the decline in Arctic sea ice extent."

From the March 21 edition of NPR's Morning Edition:

MONTAGNE: Former Vice President Al Gore goes to Capitol Hill today to testify on climate change. Gore has championed the issue of global warming for decades, and he has books and an Oscar-winning documentary to his credit.

Now that he is firmly in the spotlight on this issue, so are his detractors. They include some scientists who are concerned about global warming but have raised questions about Al Gore's data and some of his conclusions. We've asked NPR science correspondent Richard Harris to help us sort through some of the questions. Good morning, Richard.

HARRIS: Good morning, Renee.

MONTAGNE: Would you say that Al Gore -- given all of his history with this subject -- is a credible voice on global climate change?

HARRIS: Well, he is a layperson, he is not a scientist, and he's careful to say that. But that said, he does get the big picture very well. Most scientists say he really can see the forest for the trees, as one person put it.

Human activities are contributing to climate change, those changes will become more pronounced as the time goes on, and it is possible that those changes could be severe. But that said, scientists do quibble a little bit about some of the facts that he draws to make those arguments.

MONTAGNE: Give us some examples, then, of some of the concerns that scientists have.

HARRIS: OK. Well, for example, I saw Al Gore give a talk at the American Geophysical Union meeting in San Francisco last December, and he was cheered by this enormous audience of scientists, who were really excited to hear his message that, you know, it's time to take global warming seriously, et cetera, et cetera.

But after the talk, a couple of them came up to me and said, you know, “He didn't exactly get the science right,” in the sense that, Gore said that Arctic ice could be gone entirely in 34 years, and he made it seem like a really precise prediction. And there are scary predictions about what's going to happen to Arctic sea ice in the summertime, but no one can say “34 years.” That just implies a degree of certainty that's not there. And that made a few scientists a bit uncomfortable to hear him say that, making it sound so precise.