This week, a United Nations panel on climate change issued one of its most urgent warnings to date, explaining that unless major changes to greenhouse gas emissions are made within the next few years, it will become extraordinarily difficult to ward off the worst impacts of climate change.
“We cannot afford to lose another decade,” Ottmar Edenhofer, a German economist and co-chairman of the committee, told The New York Times.
With the time to cut emissions running out, the Obama administration has seized upon the hope that greenhouse gasses can be cut dramatically by switching from coal to natural gas, because gas gives off half as much carbon dioxide as coal when it’s burned. Indeed, when the EPA published its annual greenhouse gas inventory this Tuesday, it credited a switch from coal to natural gas with helping to cut carbon emissions nationwide.
But a new scientific paper, also published Tuesday in the prestigious peer-reviewed journal Proceedings of the Natural Academy of Sciences, further upends the notion that the current shale gas drilling rush is truly helping the U.S. cut its total greenhouse gas emissions.
In fact, the evidence suggests, the Obama administration has understated the full climate impacts of natural gas, focusing too much on only carbon dioxide and failing to take into account another key greenhouse gas: methane.
The paper, the first to directly measure methane plumes above natural gas drilling sites in Pennsylvania’s Marcellus shale, recorded methane leaks far more powerful than EPA estimates. Methane is especially important because its global warming effects are at their strongest during the first 20 years after it enters the atmosphere — in other words, during the small window of time identified as crucial by the U.N.’s climate panel.