Compared to past estimates by the Environmental Protection Agency and other organizations, emissions of the greenhouse gas methane are about 1.5 times higher across the U.S. and up to 2.7 times higher in the south-central region of the country, reports a new study published in the Proceedings of the National Academy of Sciences. Unlike carbon dioxide, it’s not emitted in direct proportion to fossil fuel uses like driving your car. Instead, it wafts into the atmosphere in varying degrees from several sources including oil and gas extraction, landfills, wastewater treatment…and cows. Well, not just cows, but all ruminant animals, like sheep, buffalo, and goats. They each have special digestive systems that transform plant materials like grass into nutritious food. The byproduct of that process is lots of gas, which is largely made up of methane (there’s no such thing as a free lunch, right?). And while one cute little cud-chewer won’t cause a methane meltdown, the U.S. alone is home to roughly 100 million cattle, which account for about 20% of our methane emissions. That’s a lot of gas, but there’s a silver lining to this smelly story: Even though more than 60% of methane emissions come from human activities like raising livestock, the stuff decomposes from the atmosphere in just 12 years. In other words, we have the ability to drastically alter the amount of methane that’s pumped into the atmosphere, and the changes we make will take effect quickly, says Marc Fischer, head of the California Greenhouse Gas Emissions Measurement Project at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory. Right now, agricultural scientists are developing ruminant feeding and waste management methods that produce less methane, Fischer says. But you don’t need to wait for these expert solutions to help mitigate the problem. The simplest way to start fighting global emissions right now is by eating more plant-based foods and less meat and dairy. (If a family of four skipped meat and cheese for just one day a week, that’s the equivalent of taking your car off the road for more than a month!) When you do buy meat, try to choose grass-fed varieties, which may produce fewer emissions than grain-fed meat. What’s more, buy just the amount that your family will eat to minimize waste: Surprisingly, uneaten meat accounts for more than 20% of meat’s greenhouse gas emissions, estimates the Environmental Working Group. More from Prevention: 10 Ways To Fancy Up Your Veggies
