by Katie Brown
Recently, researchers from Germany and the United States released a report that uses satellite readings to claim that methane leakage rates in the Bakken and Eagle Ford shale formations are astronomically high. In fact, the researchers claim the leakage rates could be anywhere from three to 17 percent, but settle on around 10 percent as an estimate. That’s one of the highest readings to date, which raises more than a few red flags, considering that the best available science has shown very low methane emission rates. Additionally, the U.S. Environmental Protection Agency has found that methane emissions have been dramatically reduced as natural gas production has soared.
Given those red flags, it’s useful to conduct a deeper dive into this latest report to see how the researchers came to a conclusion so far divergent from the current science.
For instance, consider the chart below, taken directly from the study, which shows methane emission increases from the period of 2006 to 2008 and the period of 2009 to 2011. The researchers drew boxes around three major shale producing areas – the Bakken, the Eagle Ford, and the Marcellus:
But what the researchers did not discuss – and what is clearly visible in the image they presented – is the fact that methane emissions increased during those same years over extended areas of the United States – including Minnesota, northern Illinois, and Nebraska – where there is little to no oil and gas production. That’s important information, especially considering that from “top-down” measurements from satellites, the researchers have no way of telling where the methane is coming from. This is something that Manvendra Dubey, a scientist at Los Alamos National Laboratory, observed. As ClimateWire reported,
“Dubey cautioned, however, that the scientists did not ‘ground truth’ their results by measuring emissions directly on the ground and comparing that with the space measurements, which is why their error bars are so large. Space observations cannot be used to pinpoint the source of the leaks, Dubey said.” (emphasis added)
Compare this highly uncertain method to a study by the University of Texas and the Environmental Defense Fund, which took direct measurements from 190 well sites and found low emission rates of around 1.5 percent.
Another anomaly: high discrepancies between different shale plays.
As is apparent from this graph, also taken directly from the report, there are hundreds of wells in the Permian (West Texas) and Haynesville (Northern Louisiana) plays, yet the areas around these wells show low readings of methane emissions, whereas large areas with no wells at all have much higher emissions. Something similar is apparent in their chart of the Marcellus region:
South central Pennsylvania is not a major area of activity for Marcellus Shale development, but southwestern Pennsylvania is – and yet the south central region records much higher emissions.
Curiously, the report thus focuses primarily on the Bakken and Eagle Ford shales, while downplaying the Marcellus and not evaluating the Permian or Haynesville at all. Why? Regarding the Marcellus, the researchers have this to say:
“As in the case of Bakken and Eagle Ford, enhanced values occur in the vicinity of the production areas. However, the number of quality-filtered measurements per gridcell is smaller compared to the other two formations, and the resulting patterns are thus considered less reliable. This is a consequence of the location in mountainous terrain and the close proximity to the Great Lakes, which exhibit low surface reflectance. In combination with the large expanse of the Marcellus, extending throughout much of the Appalachians, and the more spacious distribution of wells, this hampers a straightforward definition of rectangular hot spot and adjacent background areas required for the introduced mass-balance approach. For these reasons, we refrain from estimating the Marcellus emission increase quantitatively in this way. However, the enhancement in the direction of the prevailing westerlies for the rectilinear polygonal region shown in Figure 5 would be consistent with a methane increase of about 17 mgCH4 m−2, which is similar to the enhancements Em and Ez obtained for Bakken and Eagle Ford.”
The researchers admit that they can’t derive accurate results for the Marcellus, but then speculate – based on winds – that they would come to the same results as they found in other plays anyway.
But that still leaves a question unanswered: why did the researchers not seriously consider the data from the Permian or Haynesville shales, which showed much lower readings? According to the report, the rig count is “also the most likely reason why the enhancement patterns over the Permian basin and gas-dense Haynesville region are less clear than those of the Bakken and Eagle Ford formations (Figure 4), despite prolific total production from these regions.” The report goes on to say:
“The Permian basin is more mature than the younger plays, Bakken and Eagle Ford, with production and rig count virtually stagnating at high levels, whereas in Haynesville increasing production is concomitant with decreasing rig count, indicating increasing production efficiency with unknown impact on the emission trend [U.S. Energy Information Administration, 2014a]. One possible reason for this improved efficiency is that it pays off in the long run to invest in new technologies to reduce yield-decreasing fugitive emissions in natural gas systems, whereas in the tight oil production leakage of natural gas is typically not of primary interest in terms of profitability, because it is not the targeted resource itself and only used as an auxiliary agent to provide oil flow.”
The implication is that producers in the Eagle Ford and Bakken are employing less drilling efficiency – except that the U.S. Energy Information Administration also found that the Eagle Ford Shale is “leading in increased production of oil per rig,” with the Bakken at a close second for drilling efficiency. Drilling efficiency is something that’s occurring in all the major shale plays across the United States, so there’s no reason to single out the Bakken and Eagle Ford on that point. Are the researchers using speculation to cancel out data sets that don’t mesh with their theories?
The report also focuses heavily on research that purports to find high emission rates. For instance, here’s how the second half of the opening paragraph reads:
“However, the climate benefit from shifting away from coal is offset by fugitive methane release during the fracturing, production, and distribution process [Howarth et al., 2011; Alvarez et al., 2012; Brandt et al., 2014; Jackson et al., 2014]. This is because methane is the second most important anthropogenic greenhouse gas, being 34 times more potent per unit of mass than CO2 when including carbon-climate feedbacks and considering a time horizon of 100 years [Intergovernmental Panel on Climate Change, 2013].
In contrast to conventional gas and oil production, a significant amount of methane is already emitted during well completion [Howarth et al., 2011].”
In other words, the researchers quote known anti-fracking activists Robert Howarth and Anthony Ingraffea, and their flawed report on methane, as arbiters of fact on methane leaks – even though the report has been completely debunked by university researchers and climate scientists. Even President Obama’s former Secretary of Energy, Steven Chu — a Nobel Prize-winning physicist — said of the Ingraffea/Howarth study: “we didn’t think it was credible.”
Reports from MIT, the University of Maryland, multiple reports from the U.S. Department of Energy, Carnegie Mellon and even Cornell University have contradicted Howarth’s and Ingraffea’s research, finding methane leakage rates that are far below what they have claimed. And, of course, the University of Texas/Environmental Defense Fund study found low methane emissions rates, while the Environmental Protection Agency has documented dramatic decreases in methane emissions that coincide with huge increases in production. EPA’s latest Greenhouse Gas Reporting Program release shows that methane emissions from hydraulically fractured natural gas wells have decreased by an amazing 73 percent.
It’s little wonder that Howarth – who in 2012 signed a “pledge of resistance” to hydraulic fracturing with activists like Bill McKibben and Josh Fox, and recently went on record saying “On the issue of divestment…We need to move quickly away from all fossil fuels” – was almost gleeful at the release of this latest report. As Climatewire reported,
Robert Howarth, a professor of ecology at Cornell University who was not involved in the study, said satellites are great for integrating information over space and time.
“This study finds the highest levels of methane emission reported yet for shale gas, confirming that shale gas emissions are substantially greater than from conventional natural gas,” he said via email.
Overall, it’s difficult to get past how the report so casually ignores or glosses over its own readings of low methane emissions where oil and gas production is soaring, while still claiming a direct link between high methane emissions and oil and gas production. The report also fails to explain adequately why there are high readings of methane emissions in areas where there is no shale production occurring at all, beyond the “wind theory” that the emissions have been blown in from the producing regions.
Studying methane emissions is an important process, and the results of such studies have the potential to impact U.S. oil and gas production in profound ways. With the EPA still considering how (or if) it will regulate methane emissions, every study must be closely analyzed and carefully scrutinized. In the case of this latest study, crucial omissions and the reliance on shaky research unfortunately raise more questions – about the study itself – than any “answers” that may have otherwise been gleaned.
