Why beef may not be such a global warming villain
Unlike the popular belief, Indian cattle and buffalo cause only a minuscule increase in greenhouse gas emissions
This year’s Golden Globes and Critics’ Choice Awards in the US served only plant-based food as a way of acknowledging the role played by meat in warming the earth. Joaquin Phoenix, who won Best Actor in a Motion Picture—Drama Award at the Golden Globes, had persuaded the organizers to go vegan, and thanked them for their support in his victory speech. Meat produces more greenhouse gases per calorie than most vegetarian food, and beef is the worst offender of all. That is because cows emit the extremely potent greenhouse gas, methane (CH4), from a digestive process known as enteric fermentation.
The environmentalist battle against meat in general, and beef in particular, which originated in the US and Europe, resonates within India among people not generally known for their green activism. For instance, in the aftermath of last year’s Amazon rainforest wildfires, many of which were blamed on farmers clearing land for pasture, the vegetarian banker Uday Kotak tweeted: “I value freedom of choice but vegetarianism is good for the planet. Beef at dinner is as polluting as driving 160km. Livestock are responsible for more greenhouse emissions than the entire aviation sector. Happy Dussehra!"
Kotak announced no steps to mitigate his own carbon footprint while recommending vegetarianism to meat eaters. Since he compared emissions from livestock to those of aviation, here is some food for thought. An economy round-trip flight from Mumbai to London emits the equivalent of 2.16 metric tonnes of carbon dioxide (CO2) per passenger. A first-class seat on the same flight creates over four times that amount—in keeping with the allotted space—8.62 metric tonnes. Travelling economy instead of first on a long-haul flight would save the equivalent of six lifetimes worth of an average Indian’s consumption of beef, and three years worth of the average Indian’s total carbon emissions. Still, I don’t expect to see an Indian billionaire seated next to me in cattle class any time soon.
Unlike non-dairy cows in Europe, Oceania and the Americas, Indian cattle are not raised exclusively for meat. They labour on farms or produce milk for human consumption and are slaughtered (in the states where it is legal) at the end of their productive lives. The dual purpose of Indian zebu and water buffalo makes their meat relatively cheap. The poorest 10% of Indians eat twice as much beef and buff as the richest 10%, though it is a meagre amount in itself. To target that meat is potentially to snatch a rich source of complete protein from the most under-nourished residents of a profoundly protein-deficient nation.
The greatest deception related to beef involves an apples and oranges comparison between the CH4 emitted by ruminants and the CO2 produced by burning fossil fuels. This is expressed as an equivalence between 1 unit of methane and 25 units (sometimes 28 units) of CO2. The equivalence fails to recognize that methane from animals is one component in a short-term cycle. Carbon-rich grasses and plants are consumed by grazing ruminants. Microbes in the animals’ digestive systems convert parts of those plants into methane, which the animals expel through belching, flatulence and defecation. Within a few years, the methane combines with oxygen in the air to form carbon dioxide and water vapour. The CO2 is absorbed by plants during photosynthesis, completing the cycle. It is a loop that has been repeated constantly since ruminants first appeared on the planet.
Fossil fuels have never been part of such a cycle. They are created by the action of heat and pressure on long-buried remains of carbon-based life forms, mainly algae and zooplankton. The carbon in the petroleum we use comes from zooplankton that perished between 65 and 550 million years ago, long before modern humans or their ancestors walked the earth. The extraction and burning of fossil fuels, resulting in the release of carbon sequestered for millions of years, is an apocalyptic event rather than a natural process.
Methane in the atmosphere has a half life of around seven years, which means it diminishes by 50% every seven years. The warming effect of CH4 expelled by a cow today will begin to fall inside a decade, and drop continuously thereafter. Carbon dioxide from fossil fuels, however, unlike the carbon dioxide created from ruminant methane, is non-cyclical and cumulative.
Therefore, when estimating national carbon footprints, CO2 ought to be treated as a gross quantity, while CH4 emissions from livestock ought to be calculated as net additions. To explain this schematically, let us suppose that each molecule of methane persists in the atmosphere for exactly 40 years. This is a legitimate presumption, since methane’s effect tails off substantially four decades out. This would mean that all the methane produced by Indian cows and buffaloes in 1979 disappeared in 2019. It was replaced by the methane emitted by Indian bovines in 2019. The difference between those two quantities is what should count towards India’s greenhouse emissions for the year. In the case of thermal plants, on the other hand, all the carbon dioxide they produced by burning coal in 1979 is still hanging around in the atmosphere, and what they spew this year will only add to it.
How do the US and India perform in a scenario where methane from livestock is treated as a net quantity? Incredibly, the US cattle industry produced less methane in 2017 than it did than in 1979, according to the UN’s Food and Agriculture Organization. India’s bovine population grew from 242 million in 1977 to 302 million in 2019, an increase of 25%. We can assume methane emissions changed by a proportionate amount. In the same period, the country’s population grew from 650 million to 1.3 billion, a rise of over 100%. Our per capita carbon emissions surged from 0.43 metric tonnes to 1.94 metric tonnes between 1977 and 2018. That is an increase of 350%, and if one factors in the doubling of the population, it means our total carbon emissions in the period burgeoned by more than 700%. Over the past decade, Indian CO2 emissions have risen by an average of 6%, the fastest of any major energy consuming nation.
Methane concentrations in the atmosphere have climbed worryingly in recent years, but there are a dozen sources of the gas other than bovine enteric fermentation which could be culpable. The bottom line is that Indian cattle and buffalo place little additional burden on the environment each year, accounting for only a minuscule increase in greenhouse gas emissions.
While every gram of greenhouse gases counts, and the climate crisis demands an all-hands-on-deck approach, focusing on the 25% increase in methane emissions rather than the 700% increase in CO2 emissions suggests something other than environmental concern is driving the debate.
That “something" is an aversion to killing or mistreating sentient beings among vegans like Joaquin Phoenix, and traditional practices grounded in caste in the case of most Indians. These beliefs command respect as subjective convictions, but become disingenuous when they wear the garb of objective environmentalism and wield CH4 as a weapon with which to batter other peoples’ food habits.
Girish Shahane writes on politics, history and art.
FIRST PUBLISHED17.01.2020 | 11:11 AM IST