Landfills across America are releasing far more methane, a potent planet-warming gas, than we previously thought.
A study published in the journal Science found that our nation's dumps are releasing almost three times more methane than estimates from the Environmental Protection Agency indicate. It's a discovery that could have major implications for our climate and our communities.
What's happening?
By flying planes over roughly 20% of the nation's 1,200 large, open landfills, researchers discovered that over half had sizable methane plumes, which sometimes lasted for months or years.
This suggests that something has gone awry at these sites, such as big leaks of trapped methane from layers of long-buried, decomposing trash.
"You can sometimes get decades of trash that's sitting under the landfill," said study lead Daniel H. Cusworth, a climate scientist at the University of Arizona. "We call it a garbage lasagna."
Why are landfill emissions concerning?
When our vegetable scraps and old appliances end up buried in landfills, they decompose without oxygen, releasing methane. Over a 20-year period, methane's warming effect is a whopping 80 times more powerful than carbon dioxide, according to Stanford University's Doerr School of Sustainability.
The EPA already considers landfills the third-largest source of human-caused methane pollution in the United States, equal to the yearly emissions of 23 million cars. But if landfills are emitting nearly triple previous estimates, the threat to our communities and climate is far greater than we realized.
What's being done about landfill air pollution?
Armed with this eye-opening data, landfill operators can now pinpoint and fix methane leaks from these "garbage lasagnas" of decades-old trash. Many landfills already have wells and pipes to capture leaking methane, either to burn it off or use it for electricity or heat.
Addressing leaks in this infrastructure is an important first step.
What can I do to reduce landfill air pollution?
Composting your food waste, rather than trashing it, is a super-simple way to keep methane-emitting organics out of landfills. Whether you opt for a backyard compost bin or sign up for a local composting service, you'll be turning food scraps into nutrient-rich soil.
Limiting how much stuff you send to landfills helps, too. Reusing, repurposing, recycling, and repairing items extends their life and keeps them out of the dump. Together, our choices can curb the methane machines in our midst, building a safer future for our neighborhoods and our planet.
Join our free newsletter for cool news and cool tips that make it easy to help yourself while helping the planet.