- U.S. dairy industry pledged to become carbon neutral by 2050.
- Changing what a cow eats, manure digesters and selective breeding would cut emissions of methane, a greenhouse gas that’s 25 times more potent than carbon dioxide.
- Each year, a single cow burps 220 pounds of methane into the atmosphere, making cattle the biggest agricultural source of greenhouse gases worldwide.
The U.S. dairy industry is working to make milk production carbon neutral so that consumers will be able to enjoy cheese and other products guilt free.
The average cow will burp 220 pounds of methane into the atmosphere each year, making cattle the world’s biggest agricultural source of greenhouse gases. This has led environmental activists to call for consumers to use plant-based substitutes for milk and cheese, claiming that dairy cheese is five times worse for the environment than the nuts and tofu used to make vegan substitutes. The American dairy producers are fighting back with a plan to become carbon-neutral by 2050.
“We’ve embarked on something called the Net-Zero Initiative,” Jamie Jonker, vice president for sustainability and scientific affairs for the National Milk Producers Federation, told Karma. “The U.S. dairy industry is a net-carbon emitter, responsible for about 2% of the total. We aim to be at zero or even below by 2050.”
Cattle and other ruminants such as sheep, goats, and buffalo produce meat and milk through enteric fermentation — a process where microbes breakdown and ferment food in the digestive tract or rumen. Rumination produces methane, which the animals emit through belching, while the animal’s manure releases further greenhouse gases. The processing and transportation of dairy products also emit greenhouse gases.
“The majority of emissions come from the farm level, emissions from the cow’s backside, cow burps and crop production,” Jonker said. “The cow has an amazing digestive system, but those microbes emit methane. They are doing a great job of taking stuff we can’t eat and making it into milk.”
Some farmers are already curbing greenhouse gas emissions by installing manure digesters that convert cow waste into biogas and digested fiber, which has horticultural uses and as cow bedding. It also eliminates odor and reduces the threat of runoff polluting waterways.
“The manure from the animal has a great potential to emit methane, and methane digesters reduce these emissions,” Jonker said. “There are about 225 digestors at dairy farms, out of 34,000 farms in the country, which isn’t a big number. In many cases, it’s not revenue neutral, it actually costs the farmer.”
The dairy industry is also looking at changing feed to reduce the methane that comes from the cows burbs. Methane-reducing feed additives and supplements inhibit microorganisms in the rumen that are responsible for methane emissions. The additives include synthetic chemicals, natural supplements such as seaweed and fats and oil.
“There are some feed additives that are promising in changing methane emissions from the cow,” Jonker said. “One we are looking at cuts methane emissions from the cow’s mouth by up to 30%.”
Improvements in breeding, genetics and nutrition have made cattle rearing in the U.S. more efficient over the last 50 years. Improvements in America will need to be spread globally because livestock are responsible for 14.5 percent of world’s greenhouse gas emissions, according to the Food and Agriculture Organization of the United Nations.
“Getting to net-zero is a journey, a marathon not a 100-meter dash,” Jonker said. “We will probably have some dairy farms that will be carbon-neutral a long time before 2050. Some will act as carbon sinks while others will continue to be emit.”
