Testing by a scientist for the National Oceanic and Atmospheric Administration (NOAA) indicates that natural gas drilling might generate twice as much greenhouse gas as previously estimated, according to a recent report by National Public Radio (NPR).
NOAA scientist Gaby Petron saw high levels of methane in readings from an NOAA observation tower north of Denver and tied that pollution to the gas fields in northeastern Colorado, NPR reported.
"The story she stumbled into suggests that government may be far underestimating air pollution from natural gas production," NPR sated, "Her measurements, which were published in the Journal of Geophysical Research, suggest that methane, a potent greenhouse gas, is leaking at at least twice the rate reported by the industry."
NPR said that the NOAA paper was the latest volley in an intense estimate war under way in the scientific community about whether natural gas really is cleaner than the coal it's already starting to replace on the electric grid.
"We need to know a lot about methane itself, which is natural gas, if we're worried about climate change, so that we don't automatically think that gas is so much cleaner than coal," energy consultant Sue Tierney told NPR. She works at Analysis Group.
"Methane is very effective at trapping heat in the atmosphere. And already, natural gas production is the biggest manmade U.S. source of methane," NRP reported.
"Fifty years from now, are we really going to be wondering if we really screwed up because we went on this big gas boom? You really wouldn't want to be messing that up," Tierney told NPR. She says the time to study air pollution from natural gas is now, before the consumers, power plants and factories move to replace other fuels with natural gas.
After first discovering the high methane levels, Petron did a lot of on-the-ground detective work that identified the gas wells as the source of the emissions, according to NPR. "Then came the hard part: trying to figure out how much methane was leaking from the gas fields. That took a few years and a lot of input from industry and regulators. The science and calculations were complicated," NPR reported.
Petron told NPR even the lowest range of her estimate was higher than the leak rate industry and regulators were reporting. "Really, what our story is telling in our paper is the leak rate is twice what the industry thinks it is," she says.
Petron's work also suggests that the industry is underestimating its releases of other chemicals, including benzene, which, if present at high enough levels, can cause cancer. The industry reports negligible benzene emissions. But her calculations show it is likely the region's largest source of benzene.
Petron believes scientists need to play a much bigger role in measuring air pollution from natural gas production -- at well sites and compressor stations, and over entire gas fields. "I think the atmosphere, it's not lying," Petron says.
To read the NPR article, click here.