Oil and gas accidents have long emitted vast amounts of methane, a gas second only to carbon dioxide in its potential to warm the planet. Measuring such releases has been a challenge to scientists.
But on Monday a study released in the Proceedings of the National Academy of Sciences said a satellite launched by the European Space Agency, the Tropospheric Monitoring Instrument, or TROPOMI, detected and measured emissions of methane from a blowout last year in Ohio.
The study said methane from the damaged well was being released at about 120 tons per hour, about twice the rate of a widely reported 2015 gas leak at Aliso Canyon in California.
Exxon Mobil Corp's XTO Energy finally plugged the Ohio well after it had been leaking for nearly three weeks. Exxon did not immediately respond to a request for comment on the study.
Previously, satellites had to be carefully targeted to find leaks, such as in the Aliso Canyon case. But TROPOMI detected the methane leak as part of its routine patrol, setting the stage for gains in leak detection.
Steven Hamburg, co-author of the PNAS study, said the results "show the opportunity for satellites to help see and quantify emissions no matter where they are" and that methane-detecting satellites could help identify fixes.
Eventually scientists, environmental groups and some politicians hope to use satellites not only to discover methane emissions from major oil and gas accidents, but from smaller leaks from regular daily operations, such as in the North Dakota drilling fields.
Mike Bloomberg, the billionaire Democratic candidate in the 2020 presidential election, said in his climate plan released last week that he would create incentives for satellite companies to detect methane and "publicize methane leaks worldwide."
President Donald Trump's administration in August proposed scrapping Obama-era methane regulations.
Hamburg is also helping to lead a project for a subsidiary of the Environmental Defense Fund known as MethaneSAT. It is scheduled to launch its own satellite in 2022 to measure methane escapes weekly around the world, quantifying much smaller leaks.
