LONDON: In the fight against climate change, most experts focus on controlling emissions of carbon dioxide, but methane is actually the more potent greenhouse gas, even more effective at trapping heat in Earth’s atmosphere. Now, thanks to a new device, scientists are sniffing out the origins of harmful methane, helping them to better understand its role in warming the planet.
Methane gas comes from a variety of places, both natural and man-made. They range from lakes and swamps, natural-gas pipelines and deep-sea vents, to livestock and even damming beavers.
Now, researchers from MIT, along with teams from the Woods Hole Oceanographic Institution and the University of Toronto, have developed an instrument that can rapidly and precisely analyze samples of environmental methane to determine how the gas was formed. The new approach, called tunable infrared laser direct absorption spectroscopy, relies on the ratio of methane isotopes. This “fingerprint” allows scientists to differentiate between two common sources of methane: microbial and thermogenic.
Microbial sources refer to microorganisms that typically live in wetlands or the guts of animals, like cows, which produce methane as a metabolic byproduct. Thermogenic origins, on the other hand, are when organic matter buried deep within the Earth decays to methane at extremely high temperatures.
The team collected samples of methane from settings such as lakes, swamps, and natural gas reservoirs, the digestive tracts of cows, and deep ancient groundwater, as well as methane made by microbes in the lab.
