Methane Has Never Risen This Fast in the Atmosphere

There’s more methane in the atmosphere than any other time since record keeping began—and levels really spiked last year, despite the fact that we were all inside for most of the time.

On Wednesday, the National Oceanic and Atmospheric Agency said that global atmospheric methane rose to 1,892.3 parts per billion. Methane shattering records is one of those things that, at this point in our anthropogenic timeline, seems to happen every year. But what’s really troubling about this new record is that methane levels rose by a lot last year—the biggest rise in a single year since record-keeping began in the early 1980s. Methane levels shot up 14.7 ppb in 2020—compared to 8.5 ppb and 10.7 ppb in 2018 and 2019, respectively. Even those levels themselves, setting aside 2020’s bloated numbers, are worrisome. That 2019 number was more than 2.5 times the pre-industrial average, and 2018 and 2019 were the two biggest yearly increases since 2000, until 2020 smashed through their records like the Kool-Aid Man running through a wall.

“We don’t usually expect [methane emissions] to jump abruptly in a year,” Lori Bruhwiler, a scientist at NOAA, told the Financial Times. Bruhwiler called the jump “fairly surprising—and disturbing.”

Methane doesn’t last as long in the atmosphere as its partner in planet-warming crime, carbon dioxide (which, by the way, also shot up during 2020). But while it stays in the atmosphere for less time, it packs a much bigger heating punch: Methane is roughly 86 times more potent than carbon dioxide over a 20-year period.

An estimated 60% of methane released into the atmosphere is directly tied to human activities like flaring from oil and gas or animal agriculture. But humans still probably deserve a lot of the blame for the rest of that 40%. Permafrost thawing, for example, is, technically, a natural process that releases methane into the atmosphere. But with the Arctic warming at a breakneck pace, human activities had a hand in fast-tracking the permafrost meltdown happening right now.

Scientists aren’t sure what caused the crazy spike in methane last year—but some of their hypotheses don’t sound too good. First, a tiny bit of good news: Some preliminary atmospheric samples, NOAA said, suggest that the spike is from natural sources like ecosystems. But scientists say the increase could be because those natural sources of methane, like swamps and bogs, are getting warmer and emitting more as a result. Another idea: our atmosphere could be losing its ability to break down methane, like an old air conditioner that’s on its last legs. Sounds bad!

“Although increased fossil emissions may not be fully responsible for the recent growth in methane levels,” NOAA research chemist Ed Dlugokencky said in the agency’s Wednesday announcement, “reducing fossil methane emissions are an important step toward mitigating climate change.”

While methane may be with us for a shorter amount of time than its longer-lasting cousin carbon dioxide, curbing emissions of both greenhouse gases is vital to lower the temperature in the short-term as well as ensuring the world doesn’t cook slowly cook over the next few centuries. Our world’s climatic changes caused by human activity are kind of like a runaway car speeding down a hill, picking up more and more speed. And, as this spike in emissions shows, there could be nasty surprises about where it’s headed—and just how fast it’s going to get there.