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Naive question. If cattle eat on grass how can they increase CO2 emissions? I know farming will create some to run the machinery and transport the meant and mi

by xupybd 6y ago

Naive question. If cattle eat on grass how can they increase CO2 emissions? I know farming will create some to run the machinery and transport the meant and milk but isn't it a closed loop for the cattle? They eat grass for energy. They use that energy and create CO2. But the grass had to pull the same amount of CO2 out of the air to store that energy right? Is it that the other gases are more harmful or is there something I'm missing?

Turing_Machine 6y ago
That's not a naive question at all, and the answer is that they can't. Cows don't have little nuclear fusion reactors in their rumens, producing carbon from other elements, nor do they eat fossil fuels. Every atom of carbon "emitted" by a cow was taken from the atmosphere by a plant, likely a year ago at most. Now, methane is a more potent greenhouse gas than CO2, but it breaks down over time. The cycle can be perfectly "sustainable". Much of the land in the United States that is currently occupied in grazing cattle was formerly inhabited by vast herds of American bison, an animal so genetically similar to domestic cattle that they can actually interbreed, yet the methane emissions from the bison didn't bring on a global climate crisis. Why not?
- RC_ITR 6y ago
  Well for one, there are 2x as many cows in America today than there ever were bison. For 2, we “turn” cows faster by killing them to eat them (rather than letting nature sort it out). So that 2x is then multiplied by some factor For 3, our consumption habits have exported the cow to new environments where bison were not native (like Brazil).
  - Turing_Machine 6y ago
    > Well for one, there are 2x as many cows in America today than there ever were bison. (citation needed) > For 2, we “turn” cows faster by killing them to eat them (rather than letting nature sort it out). So that 2x is then multiplied by some factor Neither the absolute number nor the turnover rate matter. Only the raw amount of biomass. The turnover rate has nothing to do with the fact that essentially all the carbon emitted by the cow was recently removed from the atmosphere by a plant, making the whole process carbon-neutral. > For 3, our consumption habits have exported the cow to new environments where bison were not native (like Brazil). I limited my observation to the United States for a reason, but okay, I'll bite. How does a cow being "in Brazil" change the fact that any carbon it emits was almost certainly removed from the atmosphere by a plant within the last year, making the cow's digestion effectively carbon-neutral?
    - RC_ITR 6y ago
      Bison Carrying Capacity Peak Population Estimate: 30mn but other estimated vary, so let's call it 50mn. https://journals.uair.arizona.edu/index.php/rangelands/article/viewFile/11258/10531 https://journals.uair.arizona.edu/index.php/rangelands/artic... About 95mn head of cattle in the US. https://www.ers.usda.gov/topics/animal-products/cattle-beef/sector-at-a-glance/ https://www.ers.usda.gov/topics/animal-products/cattle-beef/... Why would I make up such a specific number? Most US beef and dairy cows also eat hay / grain that's been grown commercially (using a lot of energy to plant, fertilize, harvest & transport). It's cute to think cows just wander around grassy fields eating naturally occurring 'carbon neutral' grasses, but there's a reason one sees so many bales of hay at dairy farms. And a cow being 'in Brazil' means it's standing where the rainforest used to be.
      - Turing_Machine 6y ago
        > And a cow being 'in Brazil' means it's standing where the rainforest used to be. That's not answering my question. Any atom of carbon emitted by a cow was almost certainly removed from the atmosphere by a plant quite recently, yes? So how is that not a carbon-neutral cycle? We're talking about the specific claim that cow digestion, in and of itself, leads to increased carbon levels in the atmosphere. Clearly it does not, and cannot. Talking about the rain forest is shifting the goalposts. Note that North America has more forest land than it did a hundred years ago, largely because modern mechanized agriculture has dramatically increased the crop yield per acre, leading to marginal agricultural land being returned to forest cover. The "slash-and-burn" agricultural methods that destroy the rain forest are largely a feature of the "low tech" "traditional" "organic" farming techniques that are beloved by environmentalists.
        deleted 6y ago
        [deleted]
        RC_ITR 6y ago
        >Much of the land in the United States that is currently occupied in grazing cattle was formerly inhabited by vast herds of American bison, an animal so genetically similar to domestic cattle that they can actually interbreed, yet the methane emissions from the bison didn't bring on a global climate crisis. Why not? Bro, I'm answering your question as to why cows cause a global warming crisis and bison did not. You're intentionally being obtuse on that point though, right? Like yeah, cows may be just like bison in a very very narrow frame of reference, but bison did not get their food trucked to them & they did not cut down trees to graze (both of which are things cows require now). That's why. Period. EDIT: If you want to narrow your frame of reference even further & just talk about methane, then 1) It's not the main culprit so I guess we agree there. But again, Global Warming is a cumulative thing, so they fact that they product that methane AND require carbon emissions to exist is pretty bad. 2) Yeah, it's a crude estimate, that's why I almost doubled it to give you the benefit of the doubt.
  - hinkley 6y ago
    In 1491 it’s speculated that the levels of bison and passenger pigeon reported by settlers in North America were a population bubble created by reduced management (predation) by First Nations people. The stable populations of both may have in fact been about half of their peak. And while that doesn’t absolve us of anything, it may mean when we are building a report card for our current progress, we may be setting the bar a little high, and could be directing some of that energy elsewhere.
drewg123 6y ago
CO2 isn't the problem with cattle, its methane, which is a byproduct of their digestion. Methane is a greenhouse gas. The other issue is that grassland absorbs less CO2 than forests, and lots of forests have been cut down in favor grassland suitable for grazing animals.
- mastre_ 6y ago
  Do we know if diet plays a factor in methane production?
ANarrativeApe 6y ago
I thought the issue was not the CO2 they emit out the front but the methane(CH4) emitted from the other end. Methane apparently does an even better job than CO2 of keeping the heat in. The Royal Society's Summer Science Exhibition a few years ago featured the work of some scientists measuring the impact of different feeds on the amount of methane produced. But the real problem isn't cows, it's humans. As the sheer biomass of humans expands exponentially so do our demands. Almonds are no panacea, just ask the bees, or take a look at the water tables beneath the almond fields (groves? plantations?.
greenburger 6y ago
Much of the cow diet is actually corn and soy, especially for US beef production cattle. There are emissions from the fertilizer inputs to corn and soy as well as emissions from the transportation of corn and soy from field to cow.
- xupybd 6y ago
  Ah that makes a lot of sense. Here in NZ most of our cattle are grass fed with very little feed transportation. Some farmers do use feed pads but when they do they are being fooled by the big dairy companies putting pressure on the farmers to get the milk solid production up. The tends to mean the farms revenue goes up but the costs go way up so they increase work and decrease profit. So not many of them keep up the practice. I'm guessing our climate allows us to farm differently, as we have few droughts and warm winters.
- onecommentman 6y ago
  Highly depends on the specifics of a particular farm’s operations. Not a great generalization to make about dairy without supporting facts (that have got to be out there, so cite them).
niviachanta 6y ago
Just popping into say this is not naive! Food systems are so complicated

by xupybd 6y ago

Turing_Machine 6y ago

That's not a naive question at all, and the answer is that they can't. Cows don't have little nuclear fusion reactors in their rumens, producing carbon from other elements, nor do they eat fossil fuels. Every atom of carbon "emitted" by a cow was taken from the atmosphere by a plant, likely a year ago at most. Now, methane is a more potent greenhouse gas than CO2, but it breaks down over time. The cycle can be perfectly "sustainable". Much of the land in the United States that is currently occupied in grazing cattle was formerly inhabited by vast herds of American bison, an animal so genetically similar to domestic cattle that they can actually interbreed, yet the methane emissions from the bison didn't bring on a global climate crisis. Why not?

RC_ITR 6y ago
Well for one, there are 2x as many cows in America today than there ever were bison. For 2, we “turn” cows faster by killing them to eat them (rather than letting nature sort it out). So that 2x is then multiplied by some factor For 3, our consumption habits have exported the cow to new environments where bison were not native (like Brazil).
- Turing_Machine 6y ago
  > Well for one, there are 2x as many cows in America today than there ever were bison. (citation needed) > For 2, we “turn” cows faster by killing them to eat them (rather than letting nature sort it out). So that 2x is then multiplied by some factor Neither the absolute number nor the turnover rate matter. Only the raw amount of biomass. The turnover rate has nothing to do with the fact that essentially all the carbon emitted by the cow was recently removed from the atmosphere by a plant, making the whole process carbon-neutral. > For 3, our consumption habits have exported the cow to new environments where bison were not native (like Brazil). I limited my observation to the United States for a reason, but okay, I'll bite. How does a cow being "in Brazil" change the fact that any carbon it emits was almost certainly removed from the atmosphere by a plant within the last year, making the cow's digestion effectively carbon-neutral?
  - RC_ITR 6y ago
    Bison Carrying Capacity Peak Population Estimate: 30mn but other estimated vary, so let's call it 50mn. https://journals.uair.arizona.edu/index.php/rangelands/article/viewFile/11258/10531 https://journals.uair.arizona.edu/index.php/rangelands/artic... About 95mn head of cattle in the US. https://www.ers.usda.gov/topics/animal-products/cattle-beef/sector-at-a-glance/ https://www.ers.usda.gov/topics/animal-products/cattle-beef/... Why would I make up such a specific number? Most US beef and dairy cows also eat hay / grain that's been grown commercially (using a lot of energy to plant, fertilize, harvest & transport). It's cute to think cows just wander around grassy fields eating naturally occurring 'carbon neutral' grasses, but there's a reason one sees so many bales of hay at dairy farms. And a cow being 'in Brazil' means it's standing where the rainforest used to be.
    - Turing_Machine 6y ago
      > And a cow being 'in Brazil' means it's standing where the rainforest used to be. That's not answering my question. Any atom of carbon emitted by a cow was almost certainly removed from the atmosphere by a plant quite recently, yes? So how is that not a carbon-neutral cycle? We're talking about the specific claim that cow digestion, in and of itself, leads to increased carbon levels in the atmosphere. Clearly it does not, and cannot. Talking about the rain forest is shifting the goalposts. Note that North America has more forest land than it did a hundred years ago, largely because modern mechanized agriculture has dramatically increased the crop yield per acre, leading to marginal agricultural land being returned to forest cover. The "slash-and-burn" agricultural methods that destroy the rain forest are largely a feature of the "low tech" "traditional" "organic" farming techniques that are beloved by environmentalists.
      - deleted 6y ago
        [deleted]
      - RC_ITR 6y ago
        >Much of the land in the United States that is currently occupied in grazing cattle was formerly inhabited by vast herds of American bison, an animal so genetically similar to domestic cattle that they can actually interbreed, yet the methane emissions from the bison didn't bring on a global climate crisis. Why not? Bro, I'm answering your question as to why cows cause a global warming crisis and bison did not. You're intentionally being obtuse on that point though, right? Like yeah, cows may be just like bison in a very very narrow frame of reference, but bison did not get their food trucked to them & they did not cut down trees to graze (both of which are things cows require now). That's why. Period. EDIT: If you want to narrow your frame of reference even further & just talk about methane, then 1) It's not the main culprit so I guess we agree there. But again, Global Warming is a cumulative thing, so they fact that they product that methane AND require carbon emissions to exist is pretty bad. 2) Yeah, it's a crude estimate, that's why I almost doubled it to give you the benefit of the doubt.
- hinkley 6y ago
  In 1491 it’s speculated that the levels of bison and passenger pigeon reported by settlers in North America were a population bubble created by reduced management (predation) by First Nations people. The stable populations of both may have in fact been about half of their peak. And while that doesn’t absolve us of anything, it may mean when we are building a report card for our current progress, we may be setting the bar a little high, and could be directing some of that energy elsewhere.

drewg123 6y ago

CO2 isn't the problem with cattle, its methane, which is a byproduct of their digestion. Methane is a greenhouse gas. The other issue is that grassland absorbs less CO2 than forests, and lots of forests have been cut down in favor grassland suitable for grazing animals.

mastre_ 6y ago
Do we know if diet plays a factor in methane production?

ANarrativeApe 6y ago

I thought the issue was not the CO2 they emit out the front but the methane(CH4) emitted from the other end. Methane apparently does an even better job than CO2 of keeping the heat in. The Royal Society's Summer Science Exhibition a few years ago featured the work of some scientists measuring the impact of different feeds on the amount of methane produced. But the real problem isn't cows, it's humans. As the sheer biomass of humans expands exponentially so do our demands. Almonds are no panacea, just ask the bees, or take a look at the water tables beneath the almond fields (groves? plantations?.

greenburger 6y ago

Much of the cow diet is actually corn and soy, especially for US beef production cattle. There are emissions from the fertilizer inputs to corn and soy as well as emissions from the transportation of corn and soy from field to cow.

xupybd 6y ago
Ah that makes a lot of sense. Here in NZ most of our cattle are grass fed with very little feed transportation. Some farmers do use feed pads but when they do they are being fooled by the big dairy companies putting pressure on the farmers to get the milk solid production up. The tends to mean the farms revenue goes up but the costs go way up so they increase work and decrease profit. So not many of them keep up the practice. I'm guessing our climate allows us to farm differently, as we have few droughts and warm winters.
onecommentman 6y ago
Highly depends on the specifics of a particular farm’s operations. Not a great generalization to make about dairy without supporting facts (that have got to be out there, so cite them).

niviachanta 6y ago

Just popping into say this is not naive! Food systems are so complicated