Farming and emissions: Do the numbers stack up?
I just read an article on New Zealand’s climate commitment in the lead up to COP26 that lamented New Zealand is doing too little to reduce emissions from agriculture. Certainly, there are claims that agriculture makes up more than half the “total industry and household emissions” and even creates 48% of emissions, and more emissions than the energy sector in New Zealand.
I am a sceptic by nature, so I sought to check if it really stacks up that farming causes so many emissions? Not according this paper by Professor Robert Howarth of Cornell University:
“Several papers over the past 18 months have concluded that fossil fuels may not be cause of the latest surge in methane. However, there is very strong evidence that these papers are wrong. Several of the papers have concluded that an increase in emissions from cows and cattle is the cause. This conclusion conflicts strongly with the satellite data, which shows that the increase in global methane emissions over the past decade has come mostly from the United States: numbers of cows and cattle have decreased in the U.S. over this decade, and so this cannot be the cause.Cornell University; Oct 2017
Farming is not new, but global warming is. In the USA, before cows, there were bison (aka buffalos), and by many counts more buffalo than there are cows today. The strongest advocate I could find for the argument cows are worse than bison for methane argues there may be three times (3x) as much methane produced by cows as there was by bison. Other data suggest bison produce similar methane amounts to beef cattle.
If we look at the data, does it really add up that our greenhouse gas problem is the result of changing the species of grazing animals? Especially since methane levels do not accrue, and cattle and sheep have been around as long as a thousand years in many places.
Note also world livestock numbers, apart from goats, have not significantly increased since the 1960s, yet it is since the 1960s that we have seen the greatest rise in atmospheric carbon levels, and a huge rise in methane levels.
Is it coincidence that global methane levels have risen 30% during a time the number of cows has risen less than 15%, but natural gas (methane) consumption has risen by over 200%? Methane produced from grazing animals may not be significantly above levels in pre-industrial times, but methane consumption was insignificant in pre-industrial times.
Natural Methane From Plants And Animals Vs Fossil Fuel.
Plants And Animals Both Emit Methane and CO2, but all Energy in Food Is from Sequestration.
In fact, even trees emit methane. Nothing that reduces naturally achieves carbon sequestration, does not also emit methane. If you end everything that emits methane, we are left with nothing to fight climate change. The story is the nett effect. Yes, every animal has a nett effect of emitting, but once you include feeding the animal without resorting to feed from fossil fuels, the nett effect is sequestration.
It now seems that most of the world’s estimated 3 trillion trees emit methane at least some of the time.
Nobody is arguing that trees are therefore bad for climate and should be cut down. Indeed, in most cases, their carbon storage capability easily outweighs their methane emissions. But in a world where corporations plant trees to offset their carbon emissions, we badly need to know if their numbers add up, or if they are undermined by the complex chemistry of trees and methane.Wired.
Of course, plants also emit CO2. Natures sequestration of CO2 is all about natural food production. Food is fuel. Food can burn because it has had the O2 extracted, and you get energy when it is returned. Any production of food that can provide energy, axiomatically results in the production of oxygen, and the sequestration of carbon.
If you take an area of land thriving with plants and animals, then turn it into a barren wasteland, you will reduce CO2 and methane emissions. But please don’t, and the nett effect is devastating.
Natural Methane Does Not Accrue, and Only Increases When Crop or Herd Size Increases.
Methane is a more potent greenhouse gas than CO2, however methane breaks down over time. Less than half of methane emitted remains after a decade, which means that over the long term, a herd of animals of a fixed size will result in a constant level of methane. The methane produces some CO2 when it breaks down, so a high level of methane has still will drive up CO2 as well, but as methane from animals all comes from the atmosphere in the first place, the CO2 production will always be balanced by absorption in the food for the animals.
Note that currently plant agriculture produces around 15% of total methane, while animal agriculture produces double that at 30% of current methane production. The same points also apply to plant agriculture, in that unless crop sizes increase, methane levels remain again constant and do not accrue, and all carbon is sourced from the atmosphere initially, so does not increase atmospheric CO2 either.
Fossil Fuel Methane Could Accrue, And More Importantly, is always nett emissions.
The problem is not emissions themselves, but process that create more emissions than they sequestrate. Nett emissions.
All methane from plants and animals represents nett sequestration of carbon, or there would be no energy value in the food. The energy in food or even fossil fuel is proportionate to the sequestrated carbon that originally came from CO2. Plant and animal material can all over millions of years transform into fossil fuels because their material stores carbon.
Logically all methane as fossil fuel also resulted from the sequestration of carbon, and the production of that fossil fuel had a positive effect on the reduction of greenhouse effect. However, the positive effect happened millions and sometimes billions of years ago. Instead of agriculture, where both positive and negative happen at the same time, when we extract fossil fuel we are partly undoing the ‘good work’ done by plants and animals long ago. And because plants and animals have resulted in the sequestration of so much carbon (see carbon graph below), there is almost no limit to the amount of carbon we can return to the atmosphere by using fossil fuels.
Remember The Problem: Why Count Emissions from Cows but Not Humans?
Don’t Get Distracted: Methane Is Subterfuge and Distraction and, Deforestation and CO2 From Fossil Fuels Are the Real Problems.
Look at the chart. Notice it goes up. The problem is global warming. Temperatures increasing. Methane play no role in the temperature rising. Methane does play a role in temperatures, but it played the same role in 1980 that it plays today, because unlike CO2, the effect is not cumulative.
- Keep emitting CO2 at the same rate, and CO2 levels rise.
- Keep emitting methane at the same rate, and methane levels don’t rise.
- Methane levels only rise if the rate of production of methane increased.
- Production of methane from animals has not significant increase in the rate of production since 1980.
- Production of methane from coal and natural gas mining has increased significantly since 1980.
- Production of methane from wildfires has increased significantly since 1980.
Methane levels have increased since 2006, but scientific analysis confirms the increase is not from livestock. Agricultures biggest contribution is when areas are burnt as part of clearing to plant crops.
The worst source of methane increases come from increased mining of natural gas through fracking. But the natural gas that does not leak in raw methane form, but is instead burned as fuel, is a bigger contribution to climate change. Focus on methane leakage is a “oh, I am being good, I stopped the methane leaks” misdirection while natural gas continues to be used as fuel.
The focus on methane in general, but particularly from animals, or even plants, is a misdirection from the real problems. A classic “hey, look over there” move, while we still burn fossils fuels.
Is The Focus On Farm Animals Warranted?
We have had billions of years of plants consuming carbon from the CO2 in the atmosphere, and animals returning some of that carbon back to the atmosphere. Over those billions of years, the amount of carbon in the atmosphere has decreased steadily, as the carbon became progressively trapped underground as coal, oil and gas.
Do we seriously believe the reason carbon is so suddenly returning to the atmosphere, is because of the slow change in the animals we have farmed for centuries, and not because of the more recent and dramatic change to how we dig up and burning the coal, oil and gas? Remember, the carbon from the animals each year is the same carbon that came from the air that same year, while the carbon from the burning of fuel came from the air over millions of years.
Emissions From Farm Animals
Animals put back some of the carbon plants are taking out of the air. Fossil fuels put carbon in the air that has not been in the air for millions of years.
Going back to New Zealand. The data shows 39.6 Mt CO2 equivalent from farm animals in 2019, with a Mt being one million tonnes at 1,000kg each. Statistics from New Zealand government, state around 40 million dairy, beef and sheep at that time, which would mean 1 Mt per animal per year.
Data also indicates, that a human breaths out just over 1kg per day of CO2. Which means the 5 million people in New Zealand do contribute far less in emission than the cattle and sheep, because:
- New Zealand has less people than cattle and sheep.
- The figure for CO2 per cow/sheep average is almost 3x the figure for a human.
Breathing also creates emissions, and humans create more than sheep or cattle.
However, looking back a the worldwide data, there are less than 1/3 the number of sheep and cattle in the world as there people, so our own breathing results in more carbon emissions than come for sheep or cattle.
Also note, we don’t count humans carbon emissions from breathing. Why not?
Hello, I know that Scientist do not consider human respiration for calculating CO2 concentration because CO2 from the human are from the food.Researchgate post.
Perhaps an another reason for not counting human breathing in emissions, is we don’t want anyone suggesting reducing the number of people as a solution. However, the whole ‘from food’ is entirely valid. The carbon dioxide we breath out, comes from our food, and the original source of that carbon was from trees taking it out of the air. This is just putting back a portion of the carbon plants are taking out of the air, and at a slower rate than plants take it out, because we cannot consume food faster than it is grown. To consume food faster, there would need to be a huge store of food grown long ago.
Yet with fossil fuels, the consumption is far faster than new oil, gas and coal are formed. While there is so much fossil fuel we won’t run out anytime soon, the fossil fuel represents billions of year of oil, gas and coal being formed. It we could use half of the reserves in one thousand years, we would be undoing a million years of forming coal gas and oil per year.
Yet, it is expected New Zealand focus on reducing the number of cattle, rather than stopping burning fossil fuel?
It is Not Just Farm Animals.
Even trees emit methane. All wild animals all also produce methane. In most countries, humans have wiped out most native animals as large as cows or horses, but these animals, especially the herbivores, all were producing methane long before being displaced. The large animals that remain still also produce methane, but no despite the fact that eradicating kangaroos in Australia could result in a greater reduction of methane than eradicating the smaller number of cattle, it would not be good for the planet to eradicate kangaroos in order to reduce methane.
Note there have been claims kangaroos do not produce methane, but this is not supported by the science, although of course each kangaroo does produce less methane than a cow, partly as cows because larger, but there are more of kangaroos than cows in Australia.
A Potential ‘Big Oil’ Astroturf trap?
I have no evidence that research on cattle emissions or campaigns to reduce meat consumption as fighting climate change are sponsored by ‘big oil’, it would make sense. Consider what you could achieve if you wanted to disrupt climate action detrimental to oil and gas consumption:
- Alienating farmers and climate change would help with access to land for coal seem gas, and continued mining.
- There is an overlap between vegans and activists, and many passionate vegans as potential recruits.
- With only around 3% of the world as vegans, suggesting addressing climate change requires being vegan will supress enthusiasm towards addressing climate change.
- If you have billions to spend on ‘influencing’ opinions, then the misdirect is very convenient.
- Provide a source of ‘outrage’ for the climate deniers.
A Climate Activists Initiative That Alienates The Majority.
Perhaps this is a genuine grassroots push from amongst those most concerned about climate. There is a clear overlap between the those most passionate about climate, and the most passionate vegans.
Like many groups, vegans include many people who apply a strong confirmation bias to data. This means that the fact that cows and sheep produce as much emissions as our own breathing does, provides a new and opportune argument for campaigning against the farming of cows and sheep.
Working for two causes at the same time just has to feel better than only a single cause, and there are probably as many people in the world truly passionate about everyone being vegan as truly passionate about climate action.
This means protesting at a farm could feel more rewarding than protesting at a coal mine, or at least that protesting against farming at a farm might feel more rewarding than protesting against fracking at the farm. Lets face it, ‘saving’ some animals you can feel empathy for has to be more compelling stopping some equipment.
I can think of a forum that regularly host discussions and I could picture these two topics:
- We need to focus on fossil fuels, not cattle and sheep farms, in the fight against climate.
- How if society stops eating meat and dairy products, emissions will be significantly reduced.
The problem is, that the people who do support action on climate, do not necesarily want to become vegan.
But We Won’t Be Saved If We Don’t All Go Vegan!
An increasing number of people are vegan, and there is a trend for more people to go vegan. It would seem inevitable that, provided nothing derails civilisation in the meantime, at some point in the future substitutes will replace all meat products in the human diet. In the interim it will increasingly be normal to be vegan as more vegan food products become available.
But it should be for the right reason. It is a finite planet, supporting a finite number of animals, and we can support a larger human population if there is no population of animals that are also food. Ideally, the motivation won’t be to just reduce the total population of other animals so we can further increase the number of humans who can generate wealth for billionaires.
All of us make moral judgements about what food is morally ok eat, and what is not. Eating people is widely off limits. Most people won’t eat the most common household pets as food.
There are people with a diet of plants and selected animals, vegetarians with a diet of vegetable as well as animal products but no animals, vegans with a diet of plants and plant products, and fruitarians with a diet of plant products but not plants.
I say ‘diet’, because the point is what we intend to eat, as all of us also consume tardigrades and many other tiny animals we can’t see, but these tend to be simple organisms and are not consumed intentionally, so this is a technicality. We also consume, and sometimes must consume, a number of other living organisms that bridge the sometimes vague line between plant and animal.
It is a set of complex moral questions, with all of us left eating other living things, even if we find that unsettling. But in absolute terms, it is a question of choice, and although some people become very righteous about their moral choices, just as those in the pro-life movement. There is something to be said for pro-choice, and if possible, not enforcing moral choices on others.
The main point becomes, is this really the debate we need to have right now, before addressing climate change, if there is a genuine climate emergency?
The Reality For Climate Of Stopping Cattle, Sheep and Diary.
There is a reason we don’t count our own breathing as a component of emissions, because all of carbon in our breath, was taken out of the air in growing the food. It could be argued that didn’t eat the food, and instead buried it, then there would be less emissions, but what would happen to the land, if we were not using that land to grow food? Food crops are high yield intense agriculture with significant resources to ensure rapid growth. Land simply left vacant would not have result in as much growth, and thus less carbon would be extracted. If suddenly we were replaced by robots who burnt the same amount of fossil fuel but did not eat or breath, net carbon remain would be virtually unchanged.
The same is true of cattle, sheep and diary. If the animals suddenly did not exist, net carbon would be very much unchanged.
In a perfect world, we could turn all the land these animals graze on into special carbon sinks, I think this is highly unlikely in the real world. Some of the grazing land would need to turned over to crops for human consumption, but grazing land is usually less suitable for crops the process would be expensive. As any transition costs money, and this one would produce significant change in society, it is unclear what would happen to the rest of the land.
To have maximum impact on methane levels, we would also have to ensure the original grazing animals that displaced by cattle, such as bison in North America, or kangaroos in Australia, don’t return and reclaim their land.
The 30% of atmospheric methane could only be eliminated if:
- No additional plant agriculture is required to replace meat in our diet and people just eat less.
- Note, plant agriculture currently produces 15% of all methane.
- Livestock feed is still produced even though no longer required for livestock.
- A way to ensure simulate grazing to stimulate growth of grazing plants is found without grazing animals.
- Other grazing animals such as bison or kangaroos to not return to grazing land.
In summary it is highly questionable how significant the impact of stopping cattle, sheep and dairy would be in reality. It should produce a one time reduction in methane levels, depending on what takes their place. CO2 levels would see little change, and considering the distraction such a move would be from the real focus of fossil fuel use, the reality is that real action on climate change would most likely be significantly delayed.
The focus on ending meat consumption is not going to stop being entwined with climate action anytime soon, and while this reality does benefit the fossil fuel industry, it is significantly detrimental to the fight against climate change.
Some farming practices such as ‘battery hens’ can be deplorable, and there are many other issues it would be better if we solved. On the other hand I have a friend who keeps 4 chickens and cares for them as pets. There is some complexity, and are we risking allowing ourselves to become distracted from the core climate problem of stopping burning fossil fuels?
I am remined of a time in Australia where the ‘Green’ party blocked legislation on climate change because they wanted either a better policy or nothing, so they chose nothing. The chance never came again.
On Abbott’s first full day as Liberal leader, the Greens inexplicably delivered him an enormous strategic victory, voting with him to defeat Rudd’s Carbon Pollution Reduction Scheme. This short-sighted tactical manoeuvre allowed Abbott to begin to build the momentum that has hamstrung long-term climate action for almost a decade. Had the CPRS passed the parliament in 2009, an emissions trading scheme would likely have been operating for some years before Abbott was able to become prime minister. And it’s likely that Abbott would not have been able to build a platform to tear down such a large reform after that time.How Australia bungled climate policy to create a decade of disappointment
- *2022 Oct 10: fixed missing graphic.
- 2021 Nov 1: Initial version