
Nasa satellite used to monitor methane from landfill sites
Image credit: Dreamstime, Alamy
Observations from a Nasa satellite will be used by nonprofit group Carbon Mapper to discover the landfill sites responsible for emitting the most methane.
The Earth Surface Mineral Dust Source Investigation (EMIT) and other Nasa science instruments will be part of the global survey to detect the potent greenhouse gas.
Methane has more than 80 times the warming power of carbon dioxide over the first 20 years after it reaches the atmosphere, although it eventually dissipates at a much faster rate.
It is estimated to be responsible for roughly a quarter to a third of global warming caused by humans. But due to its relatively short atmospheric lifespan, eliminating emissions could lower warming in a much shorter time frame than carbon dioxide reduction efforts.
The aim of the new initiative is to establish a baseline assessment of global waste sites that emit methane at high rates. This information can help to support efforts to reduce the concentration of the gas in the atmosphere and limit climate change.
Methane produced by the waste sector contributes an estimated 20 per cent of human-caused methane emissions.
“Currently, there is limited actionable information about methane emissions from the global waste sector. A comprehensive understanding of high-emission point sources from waste sites is a critical step to mitigating them,” said Riley Duren, Carbon Mapper CEO.
“New technological capabilities that are making these emissions visible – and therefore actionable – have the potential to change the game, elevating our collective understanding of near-term opportunities in this often overlooked sector.”
The project will entail conducting an initial remote-sensing survey in 2023 of more than 1,000 managed landfills across the US and Canada, and in key locations in Latin America, Africa, and Asia.
EMIT is an imaging spectrometer that was installed on the International Space Station (ISS) in July 2022 to measure the mineral content at the surface of Earth’s major dust-producing regions.
To collect additional data from these regions, researchers will also use aircraft-based sensors and Arizona State University’s Global Airborne Observatory.
In October, scientists demonstrated that EMIT can also identify methane plumes from “super-emitters.”
It identified more than 50 ‘super-emitters’ in Central Asia, the Middle East and the south-western United States.
Super-emitters are facilities, equipment and other infrastructure, typically in the fossil-fuel, waste or agriculture sectors, that emit methane at high rates.
Methane absorbs infrared light in a unique pattern – called a spectral fingerprint – that EMIT’s imaging spectrometer can discern with high accuracy and precision. The instrument can also measure carbon dioxide.
After the first year of the Carbon Mapper project, researchers will conduct a broader survey of more than 10,000 landfills around the world using two satellites in the Carbon Mapper satellite programme.
Sign up to the E&T News e-mail to get great stories like this delivered to your inbox every day.