EPA says oil and gas methane emissions are higher than had been estimated; industry disputes

Oil and gas industry methane emissions are higher than previously estimated, the Environmental Protection Agency said in its annual inventory report released Friday. "The agency revised upward total methane emissions in the U.S. for the year 2013 from 636.3 million metric tons to 721.5 million metric tons of carbon dioxide equivalents, driven in significant part by increased estimates of emissions from oil and gas operations," Chris Mooney reports for The Washington Post. "And the overall methane emissions number is still higher for 2014, the most recent year in the inventory, at 730.8 million metric tons."

"Some of the most substantial upward revisions involved emissions from natural-gas and petroleum systems across the country—an emissions source that has increasingly been targeted by environmentalists, who say that the boom in domestic oil and gas production has driven greater methane emissions," Mooney writes. "According to the agency, the average increase per year due to its revisions was 12.9 million metric tons of carbon dioxide equivalents for natural gas systems (now the largest category of methane emissions), and 20.7 million metric tons for petroleum systems."

The American Petroleum Institute, a major industry group, disputed the numbers, Mooney writes. Kyle Isakower, the group’s vice president of regulatory and economic policy, told Mooney, “They’ve made a significant modification to the inventory estimates, and we believe that it is seriously flawed." (Read more)