Rethinking methane: Livestock’s path to climate neutrality

As his Twitter handle @GHGGuru suggests, Frank Mitloehner, professor and air quality specialist, Department of Animal Science, University of California-Davis, has a way of explaining what role animal agriculture plays in climate change with technical details, but makes it easily understandable.

Mitloehner was the keynote speaker at Colorado Livestock Association’s annual meeting June 3. He joined the meeting virtually and took a closer look at claims against agriculture, what other people are saying and what he says is the truth behind cattle production and climate change.

“I want to talk to you about livestock’s path to what I call climate neutrality, a topic that’s very timely because livestock is oftentimes accused of being one of the biggest culprits in affecting our climate,” he said. “Needless to say I have a beef with that.”

Mitloehner questions why there is so much confusion around livestock and greenhouse gases and livestock’s impact on the climate. He says part of the problem is how the data is presented. Comparing greenhouse gas emissions per kilogram of food product across all categories isn’t the right way to evaluate the differences. A simple comparison, say between tomatoes and beef, isn’t correct.

“Obviously, that is worse than an apples to oranges comparison,” he said. “It’s a beef to tomato comparison—comparing one of the most nutrient dense food items to one of the most watery ones. How anybody could do that is beyond me.”

When people see a global comparison of different food items and see beef’s ranking they often automatically assume it’s bad because of its ranking for methane contribution to the greenhouse gas footprint.

“A lot of methane makes up the carbon footprint for beef,” he said. “Our views on methane have changed drastically and I am spearheading the effort globally, and of course also here in the country, to make sure people understand why the way methane is quantified is inaccurate.”

Imagine if someone asked you the question—what are the greenhouse gas emissions of a car? Sounds simple right, Mitloehner said.

“If you think about that question you would probably come up with the answer, or with a follow up question,” he said.

Follow-ups could include different types of cars, makes, models, age of the car, where it’s driven, who drives the car, and whether it is electric, diesel or gasoline.

“All these questions have to be addressed before you even have a chance of answering the question of what the emissions are that are caused by a car, right,” he said. “It makes all the difference in the world, whether a cow is raised in parts of the United States or in England, or in Kenya and Ethiopia.”

Some data sets are lumped together, comparing things like beef to tomatoes or bananas.

Mitloehner said in the whole world, there’s approximately 49 giga tons of greenhouse gases that are emitted every year from all sources throughout the world.

“The United States contributes to 12% of all global greenhouse gases, that’s all sources of the United States,” he said.

Of that 12%, the lion’s share comes from fossil fuel sources used in transportation, power production and a number of other industries. Of that 0.5% is the livestock contribution. This includes production and consumption in the U.S.

“So those people who say, ‘what we need to do is change what we eat in the United States, eat less animal source foods and our climate issues will be drastically different,’” Mitloehner said. “Well, that is not the case. The lion’s share of greenhouse gases emitted by the United States are associated with the production and consumption of oil, coal and gas—in short, fossil fuels.”

In Environmental Protection Agency data starting in 1990, in the greenhouse gas inventory, beef’s contribution has been near the bottom of the list.

“The total greenhouse gas footprint of agriculture is around 10% in the United States, and beef makes up around 3%,” he said. “The reason why I show this is because some of the activists out there and, unfortunately, much of the media reports on the beef contributions to climate as a major elephant in the room when indeed it is clearly measurable. We know it’s there, but it’s certainly not what causes the main contributions of the United States to climate.”

Reducing the footprint

How can we reduce the environmental footprint of livestock? For Mitloehner, there are four paths—improve reproductive efficiency, install veterinary systems to prevent or treat disease, improve genetics of animals and plants and to feed a more energy-dense diet.

“These four tools allow us to shrink the number of livestock to historic lows,” he said. “One or several of these mitigation interventions are not occurring in much of the developing world, and that needs to change.”

While farm inputs have remained pretty stable, productivity has gone through the roof.

“That means we have learned to do much more with constant inputs, and that is the centerpiece of sustainability doing more with less,” Mitloehner said. “And here we are world champions. We have nothing to hide, but for some reason many farmers think we should hide. We should not hide, we should be very proud of what we have achieved.”

Mitloehner said there are people who say agricultural productivity can never really get us out of climate change, and we need to change what we eat to solve it.

“If the entire United States—330 million Americans—were to go vegan, we will reduce the carbon footprint of this country by 2.6%,” he said. “One day less meat a week for the entire United States would reduce our carbon footprint by 0.3%.”

That’s something to think about, but for Mitloehner, it’s a minor change. He said 84% of vegans and vegetarians abandon their diet after one year.

“If there was such a sustainable and such a superior diet to follow, then more people would stick to it,” he said.

Food is the main contributing factor for environmental harm in the U.S. Most American families waste about 40% of food produced in this country. Same is true for many developed countries.

“And even more surprisingly, even in developing countries of the third world, 40% of all food is never eaten,” Mitloehner said. “It’s because farmers can’t get it off of fields. Whereas in the developed world, these food wastes occur more at the consumer level, that’s us at home and in restaurants.”

Kylene Scott can be reached at 620-227-1804 or [email protected].