Concerns about the methane problem associated with the U.S. natural gas boom are mounting with each study released. This week scientists with the National Oceanic and Atmospheric Administration (NOAA) and the University of Colorado (UC) at Boulder published a new paper on methane leakage in the journal Geophysical Research Letters. It reports an alarmingly high level of methane emissions in the Uintah Basin of Utah — 6.2 to 11.7 percent of total production for an area about 1,000 square miles. Findings are based on readings from airplane flights that measured methane in the air on a single day and estimated the proportion of those emissions that came from the oil and gas infrastructure —production, gathering systems, processing and transmission of the gas out of the region. The authors calculated the uncertainty of their measurements, finding a 68 percent chance the leak rate is between 6.2 and 11.7 percent, and a 95 percent chance it is between 3.5 and 14 percent.
This follows two other regional studies conducted by scientists at the same organizations. One released last May in the Journal of Geophysical Research reported a 17 percent methane leak rate for the Los Angeles Basin, which has received quite a bit of attention although, as I’ll explain below, the figure can be misleading. The second study, conducted over the Denver-Julesburg Basin in 2008, found 4 percent of the methane produced at an oil and gas field near Denver at that time was escaping into the atmosphere. Taken together, these studies are troubling. They should be regarded as alarm bells ringing in our ears. Action by policymakers and industry is needed now.
Any amount of methane lost from the natural gas supply chain should be eliminated whenever possible. That’s because methane retains heat much more effectively relative to carbon dioxide: Over the first 20 years, an ounce of methane traps in heat 72 times more efficiently. Even small amounts vented or released as “fugitives” – unintentional methane leaked as gas moves from the field to your doorstep – can reduce or eliminate the climate advantage we think we’re getting when we substitute natural gas for coal or oil.
