Eat Your Veggies, Offset A Whole Bunch Of GHG Emissions
In the US, we’re taught at a very young age that eating meat is a sign of prosperity, and that it’s good for your health, too. What we don’t learn in science or health classes is that industrial animal agriculture has significant impacts on greenhouse gas (GHG) emissions. Now we can add another missing ingredient to this equation — if we phase out meat and replace it with plant-based foods, we could balance out the emissions from other sectors and recover important biomass across the globe.
The industrial use of animals as a food-production technology is now known to cause negative impacts on our climate. Historically, terrestrial biomass — those living biological organisms in a given area or ecosystem — diminished as native ecosystems were transformed to support grazing livestock and the cultivation of feed and forage crops.
The resulting massive animal agriculture production now accounts for as much as a third of all anthropogenic — human-caused — CO2 emissions to date. Livestock and their supply chain contribute significantly to the formidable GHGs, methane, and nitrous oxide.
Anthropogenic activities other than eating meat directly cause GHG emissions, of course. US greenhouse gas emissions from energy and industry rose 6.2% in 2021 as the economy began recovering from pandemic lows and the nation’s coal plants roared back to life. The US and countries around the world are confronted with a monumental task: to massively cut GHG emissions, primarily from transportation and energy production.
Yet the 3 sectors of food production, transportation, and energy production could have an interesting confluence.
If the world were to end all meat and dairy production and transition to a plant-based food system over the next 15 years, that shift would prevent enough greenhouse gas emissions to effectively cancel out emissions from all other economic sectors like transportation and energy for the next 30 to 50 years.
Those conclusions are part of new research published in the journal PLOS Climate. The paper’s authors say such a habitual rethinking would “substantially alter the trajectory of global warming,” as animal agriculture is estimated to account for around 15% of global greenhouse gas emissions. The impact is greater than just direct emissions, too — 30% of the Earth’s land is used to either raise farmed animals or to grow crops to feed them. The report’s authors model that restoring or “rewilding” that terrestrial biomass to ecological health would create a massive carbon sink, capturing and storing carbon that otherwise would’ve added to climate change.
How did the researchers arrive at their conclusions? They calculated the effects of ending animal agriculture — and the high levels of methane, nitrous oxide, and carbon dioxide emissions it generates — and replacing it with a plant-only food system.
- They used publicly available, systematic data on livestock production in 2019, livestock-linked emissions, and biomass recovery potential on land currently used to support livestock.
- They compared various hypothetical dietary perturbations to a “business as usual” reference in which emissions remain fixed at 2019 levels, based on available global emissions data.
- Analyzing that data, they predicted how the phaseout of all or parts of global animal agriculture production would alter net anthropogenic emissions.
- They used a simple climate model to project how these changes would impact the evolution of atmospheric GHG levels and warming for the rest of the century.
- They modeled the recovery of biomass on land currently used in livestock production using data that estimates that the return of land currently used in livestock production to its native state would sequester, over 30 years, 215.5 Gt of carbon (equivalent to 790 Gt of CO2) in plant and non-living biomass.
The study’s authors, Eisen and Brown, also found that 90% of this emissions reduction could be achieved by just cutting the production of ruminant animals like cows, sheep, and lamb, since they emit high amounts of methane, a greenhouse gas much more potent than carbon dioxide, unlike poultry.
Another recent research study, this one in Nature Foods, resulted in similar findings. The authors say a dietary shift from animal-based foods to plant-based foods in high-income nations could reduce greenhouse gas emissions from direct agricultural production and increase carbon sequestration if resulting spared land was restored to its antecedent natural vegetation.
The conclusions were reached by simulating the adoption of the EAT–Lancet planetary health diet by 54 high-income nations representing 68% of global gross domestic product and 17% of population. Results showed that such dietary change could reduce annual agricultural production emissions of high-income nations’ diets by 61% while sequestering as much as 98.3 (55.6–143.7) GtCO2 equivalent, equal to approximately 14 years of current global agricultural emissions until natural vegetation matures.
This amount could potentially fulfill high-income nations’ future sum of carbon dioxide removal (CDR) obligations under the principle of equal per capita CDR responsibilities. The researchers argue that linking land, food, climate, and public health policy will be vital to harnessing the opportunities of a double climate dividend.
The Tenacious Grasp of GHG Emissions
No, a 15-year phase-out of meat and dairy is almost certainly not going to happen. The research cited in this article could be called an intellectual exercise that unpacks meat and dairy’s enormous impact and how we as consumers can move markets — albeit slightly — to offset GHG emissions by shifting to plant-based eating. Global governments need to step up and design policies that hold industrial animal agriculture accountable if climate targets can be tackled.
Moreover, research has determined that the world will not reach the Paris climate agreement’s target of 1.5°C or 2°C temperature rise above pre-industrial levels even if we eliminate all fossil fuel use and emissions from other sectors. But we need to draw upon all the tools in our climate toolkit.
Cutting meat and dairy production isn’t part of a cultish feelgood, treehugger, granola cruncher, left-leaning movement. It’s imperative as one of the many measures we all need to adopt to limit more global warming. Suggestions to move to a plant-based diet aren’t meant to sacrifice the livelihoods of the estimated 2 billion people, most in the global South, who raise their own animals for food and income. That’s not industrial animal agriculture — that’s self-sufficiency, which resembles our ancient ancestors’ survival approach a whole lot.
However, as more individuals adopt plant-based foods into their diets, a slow momentum is rising. Industrial animal agriculture needs to be seen for what it is — a devastating effect on our planet, not a luxury that people deserve.
Author’s note: While independent analysis confirmed the accuracy of its results, the Eisen-Brown research study in PLOS Climate was conducted largely by individuals who work for Impossible Foods.
Chip in a few dollars a month to help support independent cleantech coverage that helps to accelerate the cleantech revolution!
Have a tip for CleanTechnica? Want to advertise? Want to suggest a guest for our CleanTech Talk podcast? Contact us here.
CleanTechnica's Comment Policy