The National Academy of Sciences, for its part, has convened an expert panel to deliver a verdict on the appropriate “stabilization targets” for the nation, a report expected to be delivered later this year. Of course, perspectives on what constitutes a danger may vary depending on whether one resides in Florida or Minnesota, let alone the U.S. or the Maldives.
Keeping atmospheric concentrations of greenhouse gases below 550 ppm, let alone going back to 350 ppm or less, will require not only a massive shift in society—from industry to diet—but, most likely, new technologies, such as capturing CO2 directly from the air. “Air capture can close the gap,” argues physicist Klaus Lackner, also at Columbia, who is looking for funds to build such a device.
Closing that gap is crucial because the best data—observations over the past century or so—show that the climate is sensitive to human activity. “Thresholds of irreversible change are out there—we don’t know where,” Schneider notes. “What we do know is the more warming that’s out there, the more dangerous it gets.”
This article was originally published with the title Climate Numerology.