The Grim Origins of an Ominous Methane Surge

That is, as we polluted less—heavy industry spun down, flights got canceled, people stopped commuting—we also produced less of the pollutant that normally breaks down methane. It’s a second unfortunate and surprising consequence of cutting pollution: Burning fossil fuels also produces aerosols that bounce some of the sun’s energy back into space, somewhat cooling the climate. While it’s imperative that we decarbonize as quickly as possible, cutting out the beneficial effects of NO_x and aerosols has some unintended—and twisted—side effects.

“Burning less fossil fuels will cause there to be less OH radicals in the atmosphere, which will cause methane concentrations to go up,” says Earth scientist George Allen of Virginia Polytechnic Institute and State University, who penned an accompanying commentary on the paper but wasn’t involved in the research. “So that’s going to cut back on the effectiveness of measures to fight global warming.” 

This makes it all the more urgent for humanity to take drastic steps to reduce both methane and CO₂ emissions,…