By Jeremy Deaton
A preliminary estimate from NOAA finds that levels of atmospheric methane, a potent heat-trapping gas, have hit an all-time high.
Methane is roughly 80 times more powerful than carbon dioxide, and while it stays in the atmosphere for only around a decade, as opposed to centuries, like CO2, its continued rise poses a major challenge to international climate goals.
“Here we are. It’s 2020, and it’s not only not dropping. It’s not level. In fact, it’s one of the fastest growth rates we’ve seen in the last 20 years,” said Drew Shindell, a climate scientist at Duke University.
To gauge methane levels, scientists regularly gathered samples of air from dozens of sites around the world and analyzed them at NOAA’s Global Monitoring Laboratory in Boulder, Colorado. By comparing measurements, they were able to determine the global average. In 2019, the concentration of atmospheric methane reached nearly 1875 parts per billion, the highest level since record-keeping began in 1983.
Even more troubling, 2019 saw the second-largest single-year leap in two decades. However, this figure may change, as preliminary estimates have trended high, said Ed Dlugokencky, a research chemist at NOAA. The final numbers will likely be unveiled in November after a more detailed analysis.
“We’re still waiting to see what the final number is going to be, and it’s going to be many months before we know that,” Dlugokencky said. “But the fact that methane is increasing means it’s further contributing to climate change.”
Methane emissions primarily come from natural sources, like wetlands, and manmade sources, like farms and oil and gas wells. In wetlands, microbes excrete methane, an issue that humans can do little about. On farms, cows and sheep belch methane—a problem that people can address by raising fewer livestock.
“Eat less beef and less dairy. That’s the most straightforward thing,” Shindell said. “For the sake of our own health, we should be doing that anyway.”
The easiest way to stem methane pollution, however, is to limit its release from oil and gas drilling sites, he said. Natural gas is mostly methane, and it is prone to leaking from wells. There are essentially two ways to deal with this problem. The first is to burn the natural gas that seeps out, which turns the methane into carbon dioxide. The second is to plug the leaks.