SUN VALLEY, Idaho — Climate change and greenhouse gases have become the centerpiece of consumers’ food-buying decisions, and are a major target of activists pushing a vegan agenda.
The majority of climate scientists agree climate change is taking place, Frank Mitloehner, professor and air quality specialist with the University of California-Davis Department of Animal Science, said during a presentation on sustainability at the Idaho Milk Processors Association’s annual convention.
But the contribution of the greenhouse gas methane from cattle is emphasized by those who want to sell plant-based alternatives to animal products, he said.
The three "bad boys" of climate warming are carbon dioxide, methane and nitric oxide, which create a blanket in the atmosphere that traps heat. They differ in their potential to trap heat, with methane’s potential higher than that of carbon dioxide, but they also differ in lifespan, he said.
Carbon dioxide has a lifespan of 1,000 years, with no chemical process in the atmosphere to destroy it. Methane has a lifespan of 10 years, and it’s part of the natural carbon cycle between cattle and plants, he said.
“The amount of methane being produced equals the amount of methane being destroyed. But your ‘special friends’ end the story at how much is being emitted,” he said.
Plants need carbon dioxide and sunshine to produce oxygen and carbohydrates. Ruminant animals eat that grass, a non-human-edible resource, and transform it into food. The animals convert part of the grass to methane, which is emitted into the atmosphere, and the atmosphere converts it into the carbon dioxide used by plants, he said.
“It’s not adding additional carbon to the atmosphere. If you’re not adding additional carbon, you’re not contributing to warming,” he said.
Fossil fuels extracted from the earth and burned are putting new carbon into the atmosphere and are the main cause of human climate change, he said.
“Most scientists say that. But the 'special friends' say, ‘No, animals are the cause,’” he said.
Carbon emissions from fossil fuels are a one-way street; they accumulate in the atmosphere, he said.
“We should never compare cows to cars,” it doesn’t directly correlate, he said.
The burning of fossil fuels for electricity, transportation and industry emits 81% of U.S. greenhouse gases. All of agriculture emits 9%, and animal agriculture emits 3.9% — including the crops to feed animals, processing and transportation, he said.
“Know the numbers, equip yourself with the numbers because it’s important,” he said.
In addition, efficiencies have allowed the U.S. to shrink its herds and produce more or the same amount of food while reducing the industry’s carbon footprint, he said.
The challenge is to help developing countries achieve the same efficiencies to meet the needs of a growing population — primarily from longer life expectancy — with the same or fewer resources.
There is no additional cropland. Two-thirds of all agricultural land in the world is marginal, unable to support crops, and so it’s grazed. It’s the best and only use for that land, he said.
“Those clowns who say we should not eat meat would take two-thirds of ag land out of production,” he said.
In addition, half of all fertilizers are organic, meaning “they come from some animal’s butt,” he said.
But there are issues in global agriculture. Developing countries are increasing herd sizes and not efficiencies, adding to a negative environmental footprint.
Milk production in some of those countries is dismal, 1,000 to 2,000 pounds of milk per cow per year — compared with 23,000 pounds in the U.S.
China is losing 40% of its pre-weaned pigs, more animals than the entire U.S. herd, he said.
Their carbon footprint per unit of food is high, and that gives agriculture a black eye, he said.