Climate change — the rhetoric linking cattle to climate change seems to have quieted down in light of the pandemic, but I anticipate it will ramp up again in full force in the near future.
And while the loss of life, liberty and jobs seems to be the most pertinent of conversation topics right now, air quality, especially in major metropolis areas, has been another keen observation by many.
So what does that mean when we begin to look at the true culprits of greenhouse gas emissions?
Frank Mitloehner is a professor and air quality specialist at the University of California Davis in the Department of Animal Science.
Also known as the Greenhouse Gas Guru, Mitloehner works tirelessly to separate fact from fiction when it comes to the impact of animal agriculture on the planet. He recently spoke at the Alltech ONE Virtual Experience, and today’s blog will highlight some of the best gems from his presentation.
It is my hope that by sharing this information, we'll all be better equipped to debunk some of the misconceptions about cattle and climate. Feel free to join in on the conversation on social media by using the hashtag #ClimateNeutrality and posting images of your cattle on the range, upcycling feedstuffs into nutrient-dense beef.
What is the half-life of cow burps?
Mitloehner explains the half-life of carbon dioxide verses methane. Did you know that carbon dioxide has a half-life of 1,000 years while methane has a half-life of a decade?
“The methane that our cows put out will be gone after 10 years,” said Mitloehner. “Methane isn’t just produced, but it is also destroyed. That is a very important nuance not often considered.”
What is the biogenic carbon cycle?
“Have you ever wondered where the carbon (in the methane from cattle) comes from and where it ends up?” asked Mitloehner. “Well, the origin and the fate of that carbon is actually very important to understand. Livestock-related greenhouse gases are distinctively different from other greenhouse gasses that are associated with other sectors of society, such as the transportation sector, or other fossil fuels.”
To begin to understand the difference, Mitloehner explains the biogenic carbon cycle that occurs when cattle graze the land.
“What do plants need to grow?” he asked. “They need sunlight, water and carbon in the form of Co2. That carbon in the form of Co2 is made into carbohydrates such as cellulose or starches. And that cellulose or starch component in the feed is then ingested by the cow. So the carbon goes from atmospheric C02, to carbohydrates in the plant, to the cow’s rumen, where some of the carbon is converted into methane and is released.”
He added, “After about a decade, that methane is converted via hydroxyl oxidation back into Co2. In other words, the carbon from our methane originates in atmospheric Co2. It goes through plants and then into our animals where it’s emitted, and then that carbon goes back again into atmospheric Co2.
“This is a cycle, and that’s why it’s called the biogenic carbon cycle. If you have constant livestock herds, or even decreasing livestock herds over time, then you’re not adding new additional carbon to the atmosphere. The carbon that is emitted by our animals is recycled carbon.”
He concluded, “I’m not saying that methane doesn’t matter. It’s in the atmosphere and it’s a heat-trapping, potent greenhouse gas. But the question really is, do our livestock herds add to additional methane, meaning additional carbon in the atmosphere, meaning additional warming? If herd sizes do not increase for 10 years, then additional methane is not added to the atmosphere.”
Changing the narrative
Mitloehner said by laying this out for consumers to digest, it completely changes the narrative surrounding greenhouse gases and livestock.
And once it’s understood that cattle work in concert with nature, and that the methane released is part of a beautiful cycle, then it becomes easier to understand why comparing emissions from fossil fuels to cow burps is ridiculous.
Let’s look at fossil fuels.
“Why are fossil fuels different than biogenic carbon?” he asked. “Fossil carbon really originates in the form of fossil fuels — oil, coal, gas — which are ancient forests and animals fossilized over 100-200 million years. These fossil fuels are stored in the ground, and now we are extracting them and burning that fossil fuel in our factories, cars, trains, planes and ships. By doing so we are putting it into the atmosphere.”
He added, “This is not a cycle. This is a one-way street because the amount of Co2 that we put in the atmosphere by far overpowers the potential sinks that could take up Co2 such as oceans, soils or plants.
“So this is the main culprit of greenhouse gases in our atmosphere. I have yet to see a climate scientist who would say that cows are the primary culprit of warming. Most of them would agree that the primary culprit is the use of fossil fuels,” he said.
“However, people critical of animal agriculture will always point to cattle and other livestock species. And they feel this is a very powerful tool to ostracize animal agriculture as we know it.”
Is there a connection between COVID-19 and air quality?
There are many graphics and memes circling on social media that show how the air is dramatically cleaner now than it was before COVID-19 broke. Mitloehner offers some perspective on this air quality improvement and what it means for food producers.
“What we see there with respect to improving air quality is largely the result of a reduction in the use of fossil fuels,” said Mitloehner. “We have less cars, trains, planes, ships and factories operating, and that means we are burning less fossil fuel, oil, coal and gas. We are seeing decreases of fossil fuel-related emissions that impact air quality.”
He explained, “That’s not to be confused with gasses that stem from agriculture, for example methane or ammonia or hydrogen sulfide. These gases have not really been reduced in any major way, so we have to be careful about tooting our own horns saying that this proves that agriculture is not really the culprit because that would really mean we are comparing apples to oranges. The emissions that are being reduced are different types of emissions, so that’s the nuance that discussion deserves.”
Mitloehner offered a final take-home message.
Looking forward, Mitloehner is optimistic that during this pandemic, consumers are really demanding animal-sourced foods and he anticipates that demand will continue. To be sustainable, he said, we need to find ways to get more of the supermarket price to trickle back to the farmer. Producers must be profitable to stay in business and that’s a conversation the industry needs to continue to have.
“How can we keep our livestock producers viable and receiving a greater share of the supermarket price?” he asked. “The whole profession of a farmer has to become financially viable again.
“But then I hear statistics from the current Agricultural Census that we have 2 million farmers in this country, but 1.5 million of those are hobby farmers making less than $25,000 per year. And then you add that just 80,000 farmers produce two-thirds of all food. Now that, in addition to the information that the average age of our farmers is 60, makes me very nervous. We have to pay more attention to our food-growing sector because it is of strategic importance.”
Despite these worries, Mitloehner is optimistic for the future because of growing consumer interest in food and how it’s produced.
“Before COVID-19, people just took food for granted, but now we see people working their tails off to keep food in the supermarkets,” he said. “Why are we not really tooting the horn of people growing the food in a way that they really deserve? In my opinion, they are not getting the credit they deserve. We have to put a much greater emphasis on what these people do and how they do it.”
Mitloehner reminded producers, “This is your legacy that’s at stake.” So producers, who are experts in the field, need tell their stories and work to share information that debunks common misconceptions to really take control of their future in this business.
The opinions of Amanda Radke are not necessarily those of beefmagazine.com or Farm Progress.