Agriculture and waste are the largest sources of the greenhouse gas, which scientists say is one key to limiting catastrophic warming fast.
When it comes to cutting emissions in the food system to prevent catastrophic climate change, methane is key. Tackling carbon dioxide (CO2) emissions has long been the focus of most climate action because CO2 accounts for 80 percent of all greenhouse gas (GHG) emissions in the U.S. and can persist in the atmosphere for hundreds—or even thousands—of years. In contrast, methane makes up only about 10 percent of GHG emissions in the U.S. (and 20 percent globally) and only sticks around for about a decade.
However, its global warming potential is an estimated 25–35 times greater than CO2 over a 100-year period, and methane concentration in the atmosphere has been increasing rapidly since 2007, much faster than CO2. And yet, because of its short-term lifespan, experts say cutting methane emissions now could help prevent catastrophic short-term outcomes, as we wait for more long-term investments in CO2 emissions reductions to pay off.
In other words, if we compared responses to the climate crisis to responses to a hunger crisis, cutting methane would be emergency food aid and cutting carbon dioxide would be raising wages and ending systemic racism.
“Since methane is such a potent greenhouse gas, the nice thing about reducing [those] emissions is that you can slow warming more quickly,” said Richard Waite, a senior research associate at the World Resources Institute (WRI) who studies the food system’s climate impacts.