The Environmental Protection Agency found that the oil and gas industries emit 40 percent of all methane coming from the U.S. The industries say that number is overblown because they burn or capture escaped methane before it enters the air, but a Cornell University study released last April concluded that the EPA estimate was too low.
Schoof reports there's not enough data about exactly how much methane is released. "Even small leaks can wind up undoing most of the global warming benefit we think we're getting when we substitute natural gas for coal," said Mark Brownstein, Environmental Defense Fund natural gas and oil team director. EDF isn't opposed to fracking, but it does want to work with energy companies to reduce methane emissions. (Read more)