Methane Super Emitters in the Golden State of America

Compared to carbon dioxide, methane is a more intoxicating greenhouse gas that traps comparatively more heat than carbon dioxide. Although, point-source methane emitters are small, typically less than ten meters in diameter, however, they emit highly concentrated methane plumes. Hence, if we want to reduce the amount of methane present in the air that we’re spouting, then point source methane emitters are potential targets. But that only if we could identify them.

Scientists flew over the golden state with an airborne imaging spectrometer. To map such point emissions, they used this spectrometer to measure methane emissions. Researchers focused on various potential sources that include, oil and gas production, transmission, processing, storage, and distribution equipment, dairy-manure management sites, refineries, waste-water treatment plants, landfills and composting facilities, liquefied and compressed natural gas facilities, and gas-fired power plants. Most of the facilities aforementioned were in the San Joaquin Valley, especially dairy and the oil fields. The scientists ended up measuring emissions from around 564 different sources present at 250 distinct facilities. These methane point emitters had not examined before, as they often belch out methane sporadically or in a slightly irregular manner. To catch these emitters in action scientists, conduct flights around five times between August 2016 to October 2018.

Scientists concluded that roughly 40 percent of California’s methane emissions are from these point-source emitters instead of more significant and diffuse sources, like rice fields. Additionally, over half of these point source emissions are only from 10 percent of the sites. Emissions from landfills were the worst followed by dairies ad then the oil-gas sector. Many discrepancies were also observed between previous analysis that involved atmospheric measurement and more recent airborne spectrometry analysis. However, the one thing right out of this study is that when researchers educated facilities operators that they own methane super-emitters, they were, actually, able to reduce the emission. Four cases were due to leaking of liquefied natural gas from the storage tanks. When the researchers found about the leaks they informed the operator who then repaired the tanks. Further the airborne confirmed that methane emission halted after the repair. This constant monitoring will help mitigate methane emissions.