A New Generation of Satellites Is Helping Authorities Track Methane Emissions

Efforts to identify leaks of the harmful greenhouse gas are improving with advances in technology

An artist’s redendering of MethaneSAT, a satellite that will be launched this year and will be able to find leaks of the greenhouse gas. MethaneSAT LLC

Early last year from 512 miles above the Earth, the European Space Agency satellite identified a possible methane leak in Madrid. The gas, invisible to the human eye, can have an outsized impact on global warming, particularly in the short-term. Finding these leaks and stopping them could have immediate benefits to the climate.

The instruments aboard the Copernicus Sentinel-5P satellite, however, didn’t have the high-enough resolution to pinpoint the potential problem, but GHGSat, a Canadian company, did, so it focused its newer, sharper-eyed satellite, Iris, on the location.

Iris, a satellite the size of a microwave with a seven-figure price tag can make the invisible visible, mapping methane plumes to a resolution of fewer than 100 feet. It confirmed the ESA find, discovering a landfill leak 11 miles from the city’s center.

This past August, the company sent a companion satellite, Hugo, with Iris to take another look. They found an additional leak in a neighboring landfill. Together, the leaks at their height released roughly 19,000 pounds of methane an hour, the highest the company’s satellites have found in Europe. 

“It caused quite a stir because in Europe, methane emissions are really tightly regulated,” says Stephane Germain, GHGSat’s president. “To see emissions of that magnitude was a big surprise. That’s the kind of impact we can have.”

Methane was once considered a supporting player in global warming, but a combination of new technology and advanced understanding of the greenhouse gas has brought it into the spotlight. Over the course of just 20 years, methane can have roughly 80 times the warming impact of the same amount of carbon dioxide over the short term. The gas, which is a byproduct of modern-day manufacturing, oil refineries, landfills, livestock (though belching by cows) and more, accounts for about 30 percent of global warming today.

In Madrid, city officials were defensive, not directly replying to reporters’ questions, but saying in a written statement that the government had a contract to control “fugitive emissions.”

Hugo, Iris and a growing complement of public and private sentries orbiting overhead and scheduled for launch have opened a new era of fighting the climate crisis by tracking methane leaks from landfills, pipelines and mines. The new generation of satellites will allow better measurements of such leaks over time and help the public hold countries and corporations accountable to their promises to reduce greenhouse gases.

“The new wave of satellite monitoring capability has major implications for industry and governments,” wrote a team of Columbia University researchers in a report in 2020. “Our world is rapidly becoming a place in which methane emissions will have nowhere to hide.”

Iris Satellite
The Iris satellite undergoes electromagnetic testing. The craft, now in orbit, can map methane plumes to a resolution of fewer than 100 feet. GHGSat

Until recently, methane emissions were difficult to detect. Leaks can spew from landfills, but also from the sprawling transmission, storage and distribution systems of oil and gas production. The United States, according to the Columbia University report , has more than one million oil and gas wells and millions of miles of natural gas pipelines. Finding leaks required expensive aerial overflights or ground monitoring, whether done by private companies or government bodies like the Environmental Protection Agency. Adding satellites to the mix has been both less costly and more expansive. 

“Without the data and information that are coming off of the combined use of satellites with other assets, we would never have understood how much more serious the methane challenge is,” says Jonathan Elkind, a senior research scholar at Columbia University’s Center on Global Energy Policy and a former assistant secretary in the Department of Energy. “The level of emissions was much higher than was really understood. We were fooling ourselves as to how much methane is escaping into the atmosphere.”

That deepened understanding led to the Global Methane Pledge at COP26 in Glasgow by more than 100 countries, including the United States, Japan and Canada. They agreed to cut methane emissions overall by 30 percent by 2030 compared with 2020 levels.

“We say COP(26) was the coming-out event of methane,” says Steven Hamburg, chief scientist at the Environmental Defense Fund (EDF) who has been focused on methane over the past decade. “There was broad recognition in the COP that we have to look at the climate problem through two lenses, short-lived forces that are dominated by methane, and long-lived forces that are dominated by CO2.”

Methane in the atmosphere has been surging in recent years, according to NASA and the National Oceanic and Atmospheric Administration’s Greenhouse Gas Index. The 2020 increase, NOAA says, was the largest since measurements began in 1983.

Hamburg, Germain and Elkind describe plugging methane leaks as a welcome short-term salve in the marathon climate crisis fight. “Boy, do we ever need quick wins in the climate game because we have a lot of work that’s going to take longer and be more structural in nature,” Elkind says.

Attacking the methane problem now offers the promise of short-term returns. “Methane is by far the dominant thing because you can do something today and it will have an effect ten years from now,” Hamburg says. “CO2 is the long game.”

The International Energy Agency’s Methane Tracker report for 2020 estimated that the emissions intensity for the worst performing countries like Libya is more than 100 times higher than the best ones like Canada and Saudi Arabia. Unlike dealing with carbon dioxide, much of the technology to reduce methane exists—by monitoring, mapping and repairing leaks—and is cost-effective, Hamburg says.

Map of Methane Emissions
A map from GHGSat shows methane emissions released from a landfill in Kyrgyzstan. GHGSat

Hamburg likens the coming launch of numerous satellites to creating a single high-quality movie that anyone can watch compared to the coverage in the past, sporadic measurements from planes, on-the-ground monitoring and the occasional satellite pass. “Until now, we’ve gotten snapshots,” he says. “We are going to soon have a motion picture with a high degree of clarity of what’s being emitted and where it’s being emitted. That’s a game-changer.”

In the next two years, at least ten satellites will soar into the sky, transforming patchwork surveillance into a system where methane can’t hide. The EDF will launch one of the most important crafts, MethaneSAT, working with Harvard University and the Smithsonian Astrophysical Observatory. It will join satellites including the European Space Agency’s Sentinel 5-P, launched in 2017, the Italian Space Agency’s PRISMA, launched in 2019, and those operated by the for-profit Canadian company GHGSat sent into orbit in 2016, 2020 and 2021. 

GHGSat’s customers include landfill operators, oil and gas companies like Chevron and Royal Dutch Shell, and Canada’s Oil Sands Innovation Alliance. Those clients are looking to reduce leaks and therefore losses, and embellish their environmental bona fides. The demand for GHGSat’s data is so strong that the company will launch three satellites next summer, then six in 2023, according to Germain. 

The satellites will complement each other. Sentinel 5-P, for instance, might identify a potential problem and share the information with GHGSat, which has higher-resolution instruments. MethaneSAT will complement the others with the dual ability to make targeted measurements of sites as small as 300 feet as well as broader 124-mile path looks across large oil and gas producing regions. “We can’t estimate total methane emissions from the oil and gas industry with the existing satellites,” Hamburg says. “We’ll be able to do that with (the addition of) MethaneSAT.” 

The methane data from the satellites will be made public for free. Because no corporation or government will control the information, stakeholders will be able to view it and hold leakers responsible.

The parallel rise of data analytics made Hamburg’s high-definition methane movie possible. Kayrros, a French firm, has harnessed machine learning to corral data from the European Space Agency satellite, text sources and other location information. Last year, the United Nations Environment Program launched the International Methane Emissions Observatory, an initiative providing verified data on methane emissions globally.

“It’s not just an ecosystem of satellites,” Hamburg says. “It’s a full ecosystem of producing policy-relevant data in near real-time to give policymakers and decision-makers what they need to really make effective choices.”

That comprehensive data means more scrutiny for landfill operators and the oil and gas industry. Companies will have opportunities, Elkind says, to differentiate themselves to investors and a public concerned about the climate crisis. Exxon Mobil Corp. in September said its Permian Basin operations in Texas would be certified by a nonprofit, MiQ. That organization will assess methane leaks and will grade producers on an A to F scale based on their emissions, providing an incentive for companies to invest in methane monitoring and abatement.

“There’s the potential to provide an incentive for everybody to be more precise, more promptly fix problems, be more forthright,” he says. “That’s a powerful upside of the development of these capabilities.”

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