Atmospheric levels of methane, a powerful greenhouse gas, increased by a record amount for the second year in a row in 2021, according to US government data.
The concentration of methane in the Earth’s atmosphere jumped by 17 parts per billion (ppb) in 2021, National Oceanic and Atmospheric Administration (Noaa) monitoring found, the largest annual increase recorded since modern measurements began in 1983. The previous record increase, of 15.3ppb, was set in 2020.
While carbon dioxide emitted from the burning of fossil fuels can linger in the atmosphere and contribute towards global heating for generations, methane is far shorter lived.
Methane, however, is also far more potent as a greenhouse gas: it is 25 times more powerful at trapping heat and acts as a significant short-term driver of the climate crisis. Climate activists say that methane is a “blow torch” to the climate, compared with the gradual boil provided by CO2.
Rapid cuts in methane could help curb disastrous global heating, according to scientists, but the record increases in methane suggest it is being leaked from oil and gas drilling operations and released from agriculture at dangerous rates.
“Our data show that global emissions continue to move in the wrong direction at a rapid pace,” said Rick Spinrad, administrator of Noaa. “The evidence is consistent, alarming, and undeniable.”
Methane comes from a variety of sources, from the decay of organic matter in wetlands to the burps of cows, and it is uncertain what exactly is behind the large increases in emissions. Noaa said, however, that about a third of emissions can be attributed to the fossil fuel industry, which leaks and burns off large quantities of methane when drilling for oil and gas.
According to a powerful UN climate report released this week, methane emissions must be cut by a third if the world is to avoid catastrophic temperature increases. Scientists say that as much as 0.3C of global temperature rise could be averted if methane emissions were slashed. “Reducing methane emissions is an important tool we can use right now to lessen the impacts of climate change in the near term, and reduce the rate of warming,” said Spinrad.
Climate campaigners said the “alarming” increases in methane emissions should prompt swift action to plug methane leaks.
“Polluters’ record profits must be used to properly seal and remediate every well and fix every methane leak,” said Kassie Siegel, director of the Center for Biological Diversity’s Climate Law Institute.
“But methane reductions have to be one part of a transformative global effort to phase out deadly fossil fuels in favor of truly clean renewable energy. Anything less puts us on a catastrophic path to an unrecognizable world.”
