Until recently, carbon dioxide has earned top billing among global warming gases. Emitted when fossil fuels burn, it remains the most prevalent heat-trapping emission driving climate change. Its concentration in the atmosphere has now reached levels unseen for three million years, helping to usher in an unprecedented decline in plant and animal species, according to a recent major United Nations report. Recent science is adding another gas to the marquee: methane. Just as we are learning how desperately we need to curb this gas, the Trump administration wants to kick the oil and gas industry’s methane standards to the curb.
First, the science.
Methane is the main gas emitted in the extraction of natural gas, which has accelerated dramatically in the United States with the development of hydraulic fracturing to get at previously unreachable reserves layered under shale. Like carbon dioxide, methane is also now present at levels in the atmosphere unprecedented in human history, with an atmospheric concentration that has more than doubled since preindustrial times.
In fact, now that gas has supplanted coal as the single biggest fuel source for American electricity, it has also surpassed coal in carbon emissions since 2015. The federal Energy Information Administration says if there are no changes to policy, regulations and technology, the carbon dioxide from natural gas alone will keep America’s carbon dioxide levels at the 1990 baseline level, preventing many states from their goals of reducing emissions further.
But the picture is greatly changed when we additionally consider the consequences of methane, which was not factored into the climate models guiding the Paris climate goals of holding planetary temperature rise to 2 degrees Celsius above preindustrial levels. Methane’s full implications have only recently become a scientific priority, at least partly because of the largely positive image natural gas long enjoyed in the mainstream as a “bridge” fuel away from coal. What we do know is that, while it does not last as long in the atmosphere as carbon dioxide, methane is 86 times more efficient in trapping heat on a 20-year time scale and 34 percent more efficient over the course of a century.
Methane: Underestimated no longer
Recent data, including from NOAA, clearly show a big increase in global methane emissions in recent years, with methane emissions increasing 50 percent from 2007-2013 and with a big jump in 2018. There is still scientific uncertainty about the specific contributors to this surge in global methane emissions, with both natural and man-made sources implicated. In the US, EPA data show that natural gas and petroleum operations are the single largest contributors to methane emissions. Methane leakage from the fossil fuel supply chain in the US has been a major point of research—and uncertainty—over the last few years.
One thing is clear: Making deep cuts in methane emissions wherever possible is vital to addressing climate change.
Today in the United States, the number of states where natural gas is the top source of electricity has more than doubled, from seven in 2001 to 16 in 2017, according to the New York Times. In a similar time frame, US methane emissions were found to have shot up more than 30 percent in the last decade according to a 2016 study by researchers in Harvard University’s School of Engineering and Applied Sciences. The team found that those emissions may account for between 30 and 60 percent of the global growth in atmospheric methane observed in the last 10 years.
Not only that, a major study in the journal Science last year found that the United States vastly underestimates the amount of methane emitted and leaked by the gas and oil industry. A team led by the Environmental Defense Fund (EDF), which included researchers from many universities and NOAA’s Earth System Research Laboratory, found that the industry is responsible for at least 60 percent more methane emissions than had been previously estimated by the Environmental Protection Agency.
According to this report, some 13 million metric tons of methane is spewed into the atmosphere, wasting $2 billion and enough to fuel 10 million homes. Methane leaks even amounted to some 2.3 percent of overall natural gas production. That might not sound like much but the Environmental Defense Fund previously estimated that a leakage rate of around 3 percent would negate any carbon emissions advantage natural gas might have over coal in mitigating climate change. An even more recent study by EDF and researchers at Cornell University found methane emissions at ammonia fertilizer plants to be 100 times higher than reported by industry and far above EPA estimates.
To be sure, not all independent studies come to dire conclusions about methane. Another team of researchers at NOAA’s Earth System Research Laboratory in Boulder, Colorado this year found no large increase in US emissions. The team said prior studies, including some cited above, confused ratios of methane with ethane, the second-largest component of natural gas. The American Petroleum Institute seized upon that study, with a blogger hailing it as “good news for America.” The blogger said the study proved industry is successful at capturing methane and reaffirmed natural gas’s “major role in reducing carbon dioxide emissions.”
Even if that study is correct, the comfort it offers is small. Despite some uncertainty in measuring, a study in the Journal of Geophysical Research found that, if methane levels continue rising at current rates, climate change targets set in Paris will likely be unattainable. Making matters worse, scientists need more information to fully determine exactly where the increases in methane levels are coming from. Besides leakage in the fossil fuel supply chain, possibilities include emissions from ruminant livestock such as cattle, sheep and goats, a possible feedback loop in which increased temperatures spark a release of methane from tropical wetlands, and the changes in the atmosphere that diminish its ability to destroy methane over time.
Trump administration plows ahead with rollbacks
As scientists race to pin down answers, there is no question that the bulk of the research clearly points to the fact that this should be a time for dramatic action to curb methane emissions, even if merely to be safe rather than sorry. But the Trump administration, showing a characteristic disdain for science, is racing to repeal the Obama administration’s plan to reduce methane emissions by 40 percent to 45 percent of 2012 levels by 2025. Key among the Obama-era initiatives were rules to control emissions from new and modified wells, and leaks and flaring from public and Native lands. That was just a start as most oil and gas drilling is on private land but, importantly, it was an effort to move in the right direction as is urgently needed.
For its part, the Trump EPA, led by former coal lobbyist Andrew Wheeler, fully admits that relaxing the oil and gas regulations will increase methane emissions and “may also degrade air quality and adversely affect health.” In Wheeler’s twisted view, that is fine because he says the relaxation of regulations will save industry $484 million in compliance costs. Wheeler conveniently ignores the fact that the Obama administration estimated that tighter regulations for new and modified sources gas production sites would have yielded climate benefits of $690 million by 2025, compared to compliance costs of $530 million.
As an exclamation point, Trump recently signed an executive order making it harder for states to block new gas pipelines and the administration is proposing prison sentences of up to 20 years for pipeline protestors who attempt to block construction. At about the same time, Under Secretary of Energy Mark Menezes said the expansion of a liquid natural gas export facility in Texas was an act of “spreading freedom gas throughout the world.”
When spreading “freedom” abroad coincides with locking up protestors at home, we are at a new draconian moment in energy policy. As dismissive of science as Trump has been on carbon dioxide, his madness on methane threatens to create a prison of greenhouse gas no one can escape.
Update: This post has been updated to include additional NOAA and EPA studies on methane emissions.
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