A powerful eye in the sky is helping scientists spot “super-emitters” of methane, a greenhouse gas about 80 times more potent than carbon dioxide.
This observer is NASA’s Earth Surface Mineral Dust Source Investigation Instrument, or EMIT for short. EMIT has been map the chemical composition of dust in all desert regions of the Earth since its installation outside the international space station (ISS) in July, helping researchers understand how airborne dust affects the climate.
This is the main objective of EMIT’s mission. But it also makes another less expected contribution to climate studies, NASA officials announced on Tuesday (October 25). Instrument identifies huge heat-trapping plumes methane gases in the world – more than 50 of them already, in fact.
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“The control of methane emissions is essential to limit global warming. This exciting new development will not only help researchers better determine where methane leaks are coming from, but will also provide insight into how they can be addressed quickly,” said NASA Administrator Bill Nelson. said in a press release (opens in a new tab).
“The International Space Station and more than two dozen NASA satellites and instruments in space have long been invaluable in determining changes in Earth’s climate,” Nelson added. “EMIT is proving to be an essential tool in our toolkit for measuring this powerful greenhouse gas – and stop it at the source.”
EMIT is an imaging spectrometer designed to identify the chemical fingerprints of a variety of minerals on the Earth’s surface. The ability to spot methane as well is kind of a happy accident.
“It turns out that methane also has a spectral signature in the same wavelength range, and that’s what allowed us to be sensitive to methane,” said Robert Green, principal investigator of the EMIT, from NASA’s Jet Propulsion Laboratory (JPL) in Southern California. a press conference on Tuesday afternoon.
Green and other members of the EMIT team gave some examples of the instrument’s sensitivity during Tuesday’s media call. For example, the instrument detected a plume of methane – also known as natural gas – at least 4.8 kilometers long in the sky above an Iranian landfill. This newly discovered super-emitter pumps about 18,700 pounds (8,500 kilograms) of methane into the air every hour, the researchers said.
That’s a lot, but pales in comparison to a cluster of 12 EMIT super-emitters spotted in Turkmenistan, all associated with oil and gas infrastructure. Some of these plumes are up to 20 miles (32 km) long, and together they add about 111,000 pounds (50,400 kg) of methane to earth’s atmosphere per hour.
That’s comparable to peak rates from the Aliso Canyon leak, one of the largest methane releases in US history. (The Aliso Canyon event, which occurred at a Southern California methane storage facility, was first noticed in October 2015 and was not completely plugged until February 2016.)
EMIT spotted all these super-emitters very early on, during the instrument verification phase. It should therefore make even greater contributions as it becomes fully operational and scientists become more familiar with the capabilities of the instrument, the team members said.
“We’re only scratching the surface of EMIT’s potential for mapping greenhouse gases,” JPL researcher Andrew Thorpe said at Tuesday’s press conference. “We are really excited about the potential of EMIT to reduce emissions from human activity by identifying these sources of emissions.”
Mike Wall is the author of “The low (opens in a new tab)(Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for extraterrestrial life. Follow him on Twitter @michaeldwall (opens in a new tab). Follow us on twitter @Spacedotcom (opens in a new tab) Or on Facebook (opens in a new tab).