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Methane leakage from oil and gas facilities is among the most insidious causes of global warming, not least because it is largely unavoidable.

Many oil and gas producers have dramatically reduced the amount they release into the atmosphere. However, some oil and gas facilities still emit methane regularly, sometimes on a massive scale. But this practice is often hidden because it is difficult to spot methane plumes before they disperse and with sufficient resolution to identify the culprit.

Now that looks set to change, thanks to the work of Sudhanshu Pandey of the Netherlands Institute for Space Research in Leiden, as well as the Jet Propulsion Laboratory in Pasadena, and colleagues, who have developed a high-resolution methane tracking system by combining data from several satellites of the European Space Agency. In practice, the team can zoom in to see exactly where a leak is occurring, just as it’s possible to zoom in on almost any point on Earth using Google Maps.

In 2017, the European Space Agency launched a satellite called Sentinel-5p that can detect methane plumes anywhere on Earth. The satellite is in a sun-synchronous polar orbit that gives it full coverage of the planet every day. However, it has a resolution of about 7 kilometers (about 4 miles), which is not powerful enough to find the specific facility responsible. Commercial companies such as GHGSat offer services that can map methane plumes at a resolution measured in meters, but their data is not publicly available.

So Pandey and his colleagues decided to match the Sentinel-5p data with higher-resolution data from two other satellite systems. Sentinel-3 consists of two satellites following each other in a sun-synchronous polar orbit at 800 km (about 500 mi) with a resolution of 500 m (about 1,640 ft); and Sentinel-2 is a similar dual-satellite array in a similar orbit with a resolution of up to 20 m (about 65 ft).

None of these satellite systems are specifically designed to detect methane. However, at certain frequencies and under certain conditions, they are sensitive enough to detect the causes of methane absorption. This capability allows the team to zoom in on Sentinel-5p data to find specific culprits.

The team used two real-world cases to demonstrate the technique.

The first focuses on a single methane leak observed by Sentinel-5p on the outskirts of Moscow on the morning of June 18, 2021. Sentinel-3 data taken on the same day revealed that these were two separate methane leaks from facilities 30 km apart (about 18 feet) apart.

According to the researchers, Sentinel-2 data collected just minutes later identified two separate locations along the Gryazovetsky Ring of the Moscow Regional Gas Pipeline. “The western jet comes from a small part of the infrastructure next to the pipeline, and the eastern jet comes from the Gazprom Pereslavskoye compressor station,” they wrote.

Satellite data the next day showed the leaks had stopped. Pandey and co. conclude that these events were likely controlled releases of methane designed to relieve excess pressure in the pipeline.

However, the event released a significant amount of methane into the atmosphere at a rate that reached 269 tons (over 59,000 pounds) per hour. (By comparison, the 2022 sabotage of the Nord Stream gas pipelines in the Baltic Sea was the largest anthropogenic methane leak ever recorded, releasing 220,000 tons (485 million pounds) of methane into the atmosphere in just one month. After the initial explosion, the outflow peaked at a rate of 5,000 tons (about 11 million pounds) per hour.)

The researchers also focused on a reported release from the Hassi Messaoud oil and gas field in Algeria observed by Sentinel-5p from January 3 to January 8, 2020. Sentinel-3 and Sentinel-2 data revealed the source as a specific petrochemical facility where the methane was leaking at speeds up to 68 tons (about 150,000 pounds) per hour.

After January 9, the outflow was replaced by significant burning activity that continued until February 13, when it moved north by 150 m (about 500 ft). “Such activity is typical of gas well blowouts, where operators displace the fire location to gain access to the well and control the blowout,” the authors said in their paper.

The team says the leak lasted a total of 132 days, spewing pure methane into the atmosphere for six days. “High-resolution satellite data have identified multiple methane seepage sites in Hassi Messaoud, but they did not cause methane plumes as large as those observed on January 3-8,” Pandey and the other authors said.

This important research will continue, working to identify the world’s biggest methane polluters. Methane is broken down by sunlight and so is active in the atmosphere for only a few decades. So global action to reduce emissions now can have a significant effect in the relatively short term. Indeed, the hope is that anthropogenic emissions can be reduced by 45 percent by 2045.

The researchers’ technique should play an important role in helping to name and shame wrongdoers and allow policymakers to devise appropriate measures to prevent further leaks. It can’t happen soon enough.

Reference: Daily detection and quantification of methane leakage using Sentinel-3: a multi-scale satellite monitoring approach with Sentinel-2 and Sentinel-5p:

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