Why it matters: Greenhouse gases are the major contributing factor to global warming, and methane is much more efficient in absorbing heat compared to carbon dioxide. Methane levels in the atmosphere have been rising over the past few years, driving researchers to find a potential solution.
Methane has more than 85 times the heat absorption rate of carbon dioxide over the first 20 years in the atmosphere, and is now considered one of the main reasons for rising temperature levels felt by people all around the world. A recently published study is proposing a bacterium-based solution that could help absorb some of the methane emitted by agriculture and other human-made activities.
The study authors focused on the so-called methanotrophs, a group of naturally occurring bacteria that fuel their cellular activities by "eating" methane absorbed from air. Part of the absorbed methane is then converted into carbon dioxide (CO2), which has less powerful effects on global warming and can be even recycled in greenhouses to grow food.
The researchers discovered a particularly effective methanotroph, Methylotuvimicrobium buryatense 5GB1C, which can grow at low methane concentrations (from 200 ppm to 1,000 ppm) and exhibit greater methane consumption rates. 5GB1C could thus be a "promising candidate" for a methane removal technology at emission sites, the study says.
The rapid increase of methane concentrations in the atmosphere creates "great urgency" to develop and deploy technologies for methane mitigation, the researchers state. A methanotroph like 5GB1C could be employed around cattle herds and other sites with high methane-emitting rates, providing a way to treat emissions before they reach the atmosphere.
Current solutions, which are mostly based on decreasing greenhouse gas emissions, will likely need to work together with other mitigating strategies like methanotrophs to provide a significant reduction in global warming. After discovering the methane-eating properties of 5GB1C, lead researcher Mary E Lidstrom said, there is now a bigger barrier to implementation which is essentially technical in nature.
Creating a proper mass methane-eating solution would need thousands of high-functioning reactors, the researchers estimate. Methane treatments must first be increased 20-fold, even before seeking investment capital and public acceptance for the tech. Lidstrom said that the first pilot sites to demonstrate the new technology feasibility could be ready in three or four years.