Methane pollution in the US , was 70% higher than official estimates from the US Environmental Protection Agency (EPA) between 2010 and 2019, new research shows.

The study, published in the journal The Proceedings of the National Academy of Sciences on Monday, found that oil and gas fields in the US released 14.8 teragrams (Tg) of methane annually from 2010 to 2019. It also estimates that methane emissions from Canada and Mexico stood at 2.6Tg and 1.2Tg respectively, or 67% and 50% higher than each country’s official reports.

Researchers concluded that the US government’s current system for detecting methane leaks from fossil fuel pipes, wells and compressors is inadequate. According to CNN, several recent studies have shown similar results. Atmospheric scientists now say that the EPA needs to update its technology to get more accurate measurements.

An EPA spokesperson noted that another recent study found that 2019 levels were on par with the agency’s estimates for that year.

“The EPA continues to work through its stakeholder process to review new data from [its] Greenhouse Gas Reporting Program and research studies to assess how emissions estimates can be improved,” they said.

On the discrepancies in estimates and actual emissions in the US, lead author of the study Daniel J Jacob said via Indian climate news magazine Down To Earth: “The EPA does not account for ‘super-emitters’ – devices that emit anomalous amounts of methane because of malfunctioning equipment or poor operational practices.”

Methane findings suggest massive unmeasured emissions

Jacob and colleagues analysed surface measurements and satellite data to quantify methane emissions. His research team found that methane emissions in the US rose from 14.6Tg per annum in 2010 to 15.9Tg per year in 2014, falling to 13.6Tg per year in 2017, and spiking again to 15.6Tg per annum in 2019.

Methane emissions, which are more than 25 times as potent as carbon dioxide, increased by 9% from 2010-2014. Researchers associated this with a rise in oil and gas production by 34%, and a 27% increase in the number of active wells, as well as sustained drilling of new wells.

The drop in methane emissions from 2014-2017 was linked to a 60% reduction in the development of new wells. Total oil and gas production remained stable during the same period, likely due to a decrease in annual crude oil prices by approximately 50%.

However, methane intensity over the 2010-2019 period has been in steady decline, dropping 0.13% on average annually from 3.7% in 2010 to 2.5% in 2019. This has been attributed largely to tightened emissions standards in the oil and gas sector, the researchers concluded.

The fight against methane emissions

Methane, the primary component of natural gas and a byproduct of fossil fuel extraction, has been found to be 86 times more efficient at trapping heat in the atmosphere over a 20-year-period, compared to carbon dioxide.

In 2021, the International Energy Agency (IEA) reported that methane is responsible for approximately 30% of global warming to date. It also estimated that more than 70% of current emissions from oil and gas operations are preventable at no extra net cost to companies, because the captured gas holds more value than the cost of abatement measures.

As part of the Inflation Reduction Act (IRA), the Biden administration in March committed to reducing the release of methane into the atmosphere by signing into law the Emissions Reductions Plan. The move came after criticism from business leaders, who accused the US government of being overly lenient towards polluting organisations. The EPA, enabled by the IRA, also announced that it plans to begin charging emitters of methane up to $1,500 per tonne.