Scientists Identify Methane Hot Spots
An international team of scientists employed satellite technology to map global methane emissions. Source: NASA Unsplash
Mysteriously traveling in the air is a harmful greenhouse gas known as methane. While invisible to the naked eye, it can be found using satellite technology. Earlier this month, a study published in Science used this technology to map methane emissions across the world and showcase its proliferation in the atmosphere.
The team, led by climate researcher Thomas Lauvaux of the Laboratory for Sciences of Climate and Environment, used the TROPOspheric Monitoring Instrument–an imaging spectrometer–to measure the amount of methane in the atmosphere from 2019 to 2020. They found that ultra-emitters, the world's largest oil and gas basins, release between eight to twelve percent of international methane emissions, which equates to about eight million metric tons annually.
Over the course of two years, the company Kayrros and the group of researchers gathered meteorological data from methane plumes, which are bundles of methane released from shale gas wells. They utilized these detections to form models that led them to identify the amount of released methane. Almost 2,000 plumes were observed in total.
"Every time we had a detection, we could link it to potential gas infrastructure, and it's when we realized that a vast majority of them were actually from the oil and gas activity," Lauvaux said.
The satellites could only detect large methane events, but they still added up to a substantial amount. "You have to imagine 200 tons [of methane] an hour is an open pipeline pouring straight into the air. Sometimes, you might hear it from a mile away,” said Lauvaux. “It's massive."
Two-thirds of the methane detected originates from oil and gas production, with the top three emitters being Turkmenistan, Russia and the U.S. According to the International Energy Agency, Turkmenistan has the "fourth-largest total offshore and onshore gas reserves in the world." Lauvaux and his colleagues suggest that the Asian country will most likely increase its methane emissions two-fold.
The Environmental Defense Fund conducted a research series on methane emissions in the U.S. between 2012 and 2018, but Lauvaux and his team are the first to examine methane emissions on a global statistical scale.
"We started to think that it's really worth digging in the entire dataset…so a lot of data you have to collect," Lauvaux said.
Carbon dioxide is typically recognized as the infamous poster child of the climate change crisis, but methane is the greenhouse gas that traps more heat within the atmosphere.
Zion Klos, Assistant Professor of Environmental Science at Marist College, said methane is about 30 times more powerful than carbon dioxide. "It's really good at kind of blanketing the Earth with the greenhouse effect," he said. "Having spent time at these sites when I was working out west, I guess I'm not surprised at all because the oversight can be pretty minimal at times for some of these things, especially for an invisible gas like methane."
Simultaneously, the distribution of leaks demonstrates that the countries with ultra-emitters also have an immense amount of smaller emitters that cause just as much damage to the environment, if not more.
While remote sensing technology can evidently advance understanding, there are potential pitfalls to these devices. "We're able to do a lot more with that, but at the same time, just because you can see it in satellites doesn't mean you're going to be able to be on the site and easily identify where it's coming from," Klos said.
The satellites Lauvaux and his team used depended on sun rays to measure the amount of methane in the atmosphere, but their data was initially impacted by the varying surface properties of the land. This influence was seen when a landfill in California was detected because it was darker than the ground surrounding it.
The study also suggests that limiting ultra-emitters would lead to significant financial savings for the top emitter countries in the billions of dollars. "We essentially need the biggest economies in the world to agree to mutually put a tax or some kind of cost incentive for their economies to push away from fossil fuels," Klos said.
Just last year, a massive oil spill off the Pacific coast occurred, and a federal court ruled to block the sale of over 80 million acres of the Gulf of Mexico for offshore oil and gas drilling. With gas prices rising in the U.S and inflation soaring, the industry doesn't show much signs of stopping anytime soon.
Ironically, since the time Lauvaux and his colleagues published their study, no major oil or gas facilities have spoken out. This could be because they know they are leaking, or they would have issued legal action. Or it simply could be that they have no excuse.
Lauvaux believes planned maintenance operations are one of the roots of the issue when it comes to oil and gas leaks. He plans to expand the study and examine emissions specifically in the U.S. Since methane isn’t a long-lasting gas, it can be removed in ten years if action is taken immediately.
"[Eliminating methane] is not going to save the planet,” Lauvaux said. “But it's the first step.”