Methane Leaks From Three Large US Natural Gas Fields in Line With Federal Estimates
Tens of thousands of pounds of methane leak per hour from equipment in three major natural gas basins that span Texas, Louisiana, Arkansas, and Pennsylvania, according to airborne measurements published by a team of scientists led by the National Oceanic and Atmospheric Administration (NOAA). But the overall leak rate from those basins is only about 1% of gas production there—lower than leak rates measured in other gas fields and in line with federal estimates.
“We are beginning to get a sense of regional variation in methane emissions from natural gas production,” said lead author Jeff Peischl, a scientist with the Cooperative Institute for Research in Environmental Sciences (CIRES) in Boulder, Colorado. “The gas fields we studied for this paper produced about 20% of the natural gas in the United States and more than half the shale gas, so this moves us closer to understanding methane leaks from US natural gas production.”
Peischl works at NOAA’s Earth System Research Laboratory in Boulder, Colorado. His team’s analysis appears online today in the Journal of Geophysical Research: Atmospheres, published by the American Geophysical Union.
In the new paper, he and his colleagues used sophisticated measurements taken from a NOAA research aircraft to determine methane emissions from the Haynesville, Fayetteville, and Marcellus regions during five flights in the summer of 2013.
Overall, they found that methane leaking from gas equipment totaled about 1.1% of gas produced in those regions; estimates from the Environmental Protection Agency, based on average equipment leak rates, put that figure at about 1%.
“It is good news that our atmospheric measurements are close to the EPA estimates,” said coauthor Joost de Gouw, a CIRES scientist who also works at NOAA. “If leak rates are too high, natural gas does not compare favorably with one alternative, coal, in terms of climate impact. Where leak rates are low, the comparison favors natural gas.”