New space sensor spots greenhouse gas sources

In 2022, an imaging spectrometer developed at NASA’s Jet Propulsion Laboratory (JPL) was installed on the International Space Station. It was designed to study dust particles from arid areas and understand how their presence in the atmosphere affects Earth’s climate. Researchers are now using the instrument to detect greenhouse gas emissions.

In a recent study, they spotted methane and carbon dioxide plumes from oil and gas operations, power plants, landfills, and wastewater treatment facilities in the Middle East and Central Asia (Sci. Adv. 2023, DOI: 10.1126/sciadv.adh2391). The strengths of the technology are its fine-scale mapping capabilities and wide geographic coverage, says Andrew Thorpe, a research technologist at JPL and the study’s lead author.

The instrument captures images of Earth from space at a resolution of 60 m per pixel, scanning strips of land as the space station orbits the planet and covers an area about the size of South Africa every day. Such high resolution is necessary to detect plumes that are typically less than 1 km long and that contain high concentrations of methane and CO₂. Instruments mounted on aircraft often provide these measurements, but their coverage is limited by how far and how often they can fly. These surveys can miss emissions that tend to be intermittent.

In the first month of the spectrometer’s operation, Thorpe and his colleagues could identify CO₂ plumes from two coal-fired power plants in China that lacked continuous emission monitoring and reporting. They were also able to detect methane plumes from oil and gas operations, landfills, wastewater treatment and power plants in several countries.

“It’s an impressive system,” says Chris McLinden, an atmospheric physicist at Environment and Climate Change Canada who was not involved in the study.

Although JPL’s instrument isn’t the only space-based sensor detecting point source emissions, “it’s one piece of what will hopefully be a much larger constellation of satellites doing more or less the same thing,” McLinden says. That will help address key data gaps, he adds.